Patent Application
20090172669
This invention relates, in general, to managing customer environments to provide support for business resiliency, and in particular, to grouping resources to enable granular management of a customer's environment.
Today, customers attempt to manually manage and align their availability management with their information technology (IT) infrastructure. Changes in either business needs or the underlying infrastructure are often not captured in a timely manner and require considerable rework, leading to an inflexible environment.
Often high availability solutions and disaster recovery technologies are handled via a number of disparate point products that target specific scopes of failure, platforms or applications. Integrating these solutions into an end-to-end solution is a complex task left to the customer, with results being either proprietary and very specific, or unsuccessful.
Customers do not have the tools and infrastructure in place to customize their availability management infrastructure to respond to failures in a way that allows for a more graceful degradation of their environments. As a result, more drastic and costly actions may be taken (such as a site switch) when other options (such as disabling a set of applications or users) could have been offered, depending on business needs.
Coordination across availability management and other systems management disciplines is either nonexistent or accomplished via non-reusable, proprietary, custom technology.
There is little predictability as to whether the desired recovery objective will be achieved, prior to time of failure. There are only manual, labor intensive techniques to connect recovery actions with the business impact of failures and degradations.
Any change in the underlying application, technologies, business recovery objectives, resources or their interrelationships require a manual assessment of impact to the hand-crafted recovery scheme.
Based on the foregoing, a need exists for a capability that facilitates active management of business applications during runtime. As an example, a need exists for a facility that optimizes, during runtime, the reconfiguration of resources to meet a particular goal, such as an availability goal or other goal.
The shortcomings of the prior art are overcome and additional advantages are provided through the provision of a computer-implemented method, in which a redundancy group including one or more functionally equivalent resources of a particular type is obtained; and during runtime and in response to an occurrence of an event, there is dynamic evaluation of which resource of a plurality of resources of the redundancy group is to be used as a target for an operation to be performed.
Computer program products and systems relating to one or more aspects of the present invention are also described and claimed herein.
Additional features and advantages are realized through the techniques of the present invention. Other embodiments and aspects of the invention are described in detail herein and are considered a part of the claimed invention.
One or more aspects of the present invention are particularly pointed out and distinctly claimed as examples in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
In managing a customer's environment, such as its business environment, there is a set of requirements unaddressed by existing technology, which causes unpredictable down time, large impact failures and recoveries, and significant extra labor cost, with resulting loss of business revenue. These requirements include, for instance:
The above set of requirements is addressed, however, by a Business Resiliency (BR) Management System, of which one or more aspects of the present invention are included. The Business Resiliency Management System provides, for instance:
One goal of the BR system is to allow customers to align their supporting information technology systems with their business goals for handling failures of various scopes, and to offer a continuum of recovery services from finer grained process failures to broader scoped site outages. The BR system is built around the idea of identifying the components that constitute a business function, and identifying successive levels of recovery that lead to more complex constructs as the solution evolves. The various recovery options are connected by an overall BR management capability that is driven by policy controls.
Various characteristics of one embodiment of a BR system include:
A Business Resilience System is capable of being incorporated in and used by many types of environments. One example of a processing environment to incorporate and use aspects of a BR system, including one or more aspects of the present invention, is described with reference to
Processing environment 100 includes, for instance, a central processing unit (CPU) 102 coupled to memory 104 and executing an operating system 106. Examples of operating systems include AIX® and z/OS®, offered by International Business Machines Corporation; Linux; etc. AIX® and z/OS® are registered trademarks of International Business Machines Corporation, Armonk, N.Y., U.S.A. Other names used herein may be registered trademarks, trademarks or product names of International Business Machines Corporation or other companies.
The operating system manages execution of a Business Resilience Runtime Component 108 of a Business Resilience System, described herein, and one or more applications 10 of an application container 112.
As examples, processing environment 100 includes an IBM® System z™ processor or a pSeries® server offered by International Business Machines Corporation; a Linux server; or other servers, processors, etc. Processing environment 100 may include more, less and/or different components than described herein. (pSeries® is a registered trademark of International Business Machines Corporation, Armonk, N.Y., USA.)
Another example of a processing environment to incorporate and use aspects of a BR System, including one or more aspects of the present invention, is described with reference to
As shown, a processing environment 200 includes for instance, a central processing complex 202 coupled to an input/output (I/O) subsystem 204. Central processing complex 202 includes, for instance, a central processing unit 206, memory 208, an operating system 210, a database management system 212, a Business Resilience Runtime Component 214, an application container 216 including one or more applications 218, and an I/O facility 220.
I/O facility 220 couples central processing complex 202 to I/O subsystem 204 via, for example, a dynamic switch 230. Dynamic switch 230 is coupled to a control unit 232, which is further coupled to one or more I/O devices 234, such as one or more direct access storage devices (DASD).
Processing environments 100 and/or 200 may include, in other embodiments, more, less and/or different components.
In yet another embodiment, a central processing complex 300 (
For example, network service 302 of central processing complex 300 is coupled to a switch 308 of network subsystem 306. Switch 308 is coupled to a switch 310 via routers 312 and firewalls 314. Switch 310 is further coupled to a network service 316 of processing environment 304.
Processing environment 304 further includes, for instance, a central processing unit 320, a memory 322, an operating system 324, and an application container 326 including one or more applications 328. In other embodiments, it can include more, less and/or different components.
Moreover, CPC 300 further includes, in one embodiment, a central processing unit 330, a memory 332, an operating system 334, a database management system 336, a Business Resilience Runtime Component 338, an application container 340 including one or more applications 342, and an I/O facility 344. It also may include more, less and/or different components.
I/O facility 344 is coupled to a dynamic switch 346 of an I/O subsystem 347. Dynamic switch 346 is further coupled to a control unit 348, which is coupled to one or more I/O devices 350.
Although examples of various environments are provided herein, these are only examples. Many variations to the above environments are possible and are considered within the scope of the present invention.
In the above-described environments, a Business Resilience Runtime Component of a Business Resilience System is included. Further details associated with a Business Resilience Runtime Component and a Business Resilience System are described with reference to
In one example, a Business Resilience System 400 is a component that represents the management of recovery operations and configurations across an IT environment. Within that Business Resilience System, there is a Business Resilience Runtime Component (402) that represents the management functionality across multiple distinct Recovery Segments, and provides the service level automation and the support of creation of the recovery sequences. In addition, there are user interface (404), administration (406), installation (408) and configuration template (410) components within the Business Resilience System that enable the administrative operations that are to be performed. Each of these components is described in further detail below.
Business Resilience Runtime Component 402 includes a plurality of components of the BR System that are directly responsible for the collection of observations, creation of PSEs, policy acceptance, validation, error detection, and formulation of recovery sequences. As one example, Business Resilience Runtime Component 402 includes the following components:
1. One or more Business Resilience Managers (BRM) (412).
2. One or more Recovery Segments (RS) (414).
3. Pattern System Environments (PSEs) (416).
4. Quantified Recovery Goal (418).
5. Containment Region (CR) (420).
6. Redundancy Groups (RG) (422).
7. BR Manager Data Table (BRMD) (424).
8. BR Manager Relationship Data Table (BRRD) (426).
9. BR Asynchronous Distributor (BRAD) (428).
10. Observation Log (430).
11. RS Activity Log (432).
12. BRM Activity Log (434).
13. Transaction Table (TT) (436).
In addition to the Business Resilience Runtime Component of the BR system, the BR system includes the following components, previously mentioned above.
User Interface (UI) Component (404).
1. Business Resilience View 502
2. Topology/Definition Template Editor 504
3. Properties View/Topology Resources View/Search View 506
4. Outline View 508
BR Admin Mailbox (406) (
BR Install Logic (408) (
Availability Configuration Templates (410):
The user interface, admin mailbox, install logic and/or template components can be part of the same computing unit executing BR Runtime or executed on one or more other distributed computing units.
To further understand the use of some of the above components and their interrelationships, the following example is offered. This example is only offered for clarification purposes and is not meant to be limiting in any way.
Referring to
As a result of these conditions leading up to runtime, the following subscriptions have already taken place:
These steps highlight one example of an error detection process:
In addition to the above, BR includes a set of design points that help in the understanding of the system. These design points include, for instance:
BR is targeted towards goal based policies—the customer configures his target availability goal, and BR determines the preparatory actions and recovery actions to achieve that goal (e.g., automatically).
Availability management of the IT infrastructure through goal based policy is introduced by this design. The BR system includes the ability to author and associate goal based availability policy with the resource Recovery Segments described herein. In addition, support is provided to decompose the goal policy into configuration settings, preparatory actions and runtime procedures in order to execute against the deployed availability goal. In one implementation of the BR system, the Recovery Time Objective (RTO—time to recover post outage) is a supported goal policy. Additional goal policies of data currency (e.g., Recovery Point Objective) and downtime maximums, as well as others, can also be implemented with the BR system. Recovery Segments provide the context for association of goal based availability policies, and are the scope for goal policy expression supported in the BR design. The BR system manages the RTO through an understanding of historical information, metrics, recovery time formulas (if available), and actions that affect the recovery time for IT resources.
RTO goals are specified by the customer at a Recovery Segment level and apportioned to the various component resources grouped within the RS. In one example, RTO goals are expressed as units of time intervals, such as seconds, minutes, and hours. Each RS can have one RTO goal per Pattern System Environment associated with the RS. Based on the metrics available from the IT resources, and based on observed history and/or data from the customer, the RTO goal associated with the RS is evaluated for achievability, taking into account which resources are able to be recovered in parallel.
Based on the RTO for the RS, a set of preparatory actions expressed as a workflow is generated. This preparatory workflow configures the environment or makes alterations in the current configuration, to achieve the RTO goal or to attempt to achieve the goal.
In terms of optimizing RTO, there are tradeoffs associated with the choices that are possible for preparatory and recovery actions. Optimization of recovery choice is performed by BR, and may include interaction at various levels of sophistication with IT resources. In some cases, BR may set specific configuration parameters that are surfaced by the IT resource to align with the stated RTO. In other cases, BR may request that an IT resource itself alter its management functions to achieve some portion of the overall RS RTO. In either case, BR aligns availability management of the IT resources contained in the RS with the stated RTO.
In this design, as one example, there is an approach to collecting the required or desired metrics data, both observed and key varying factors, system profile information that is slow or non-moving, as well as potential formulas that reflect a specific resource's use of the key factors in assessing and performing recovery and preparatory actions, historical data and system information. The information and raw metrics that BR uses to perform analysis and RTO projections are expressed as part of the IT resources, as resource properties. BR specific interpretations and results of statistical analysis of key factors correlated to recovery time are kept as BR Specific Management data (BRMD).
BR maintains specific information about the BR management of each resource pairing or relationship between resources. Information regarding the BR specific data for a resource pairing is kept by BR, including information such as ordering of operations across resources, impact assessment information, operation effect on availability state, constraint analysis of actions to be performed, effects of preparatory actions on resources, and requirements for resources to co-locate or anti-co-locate.
One feature of the BR function is the ability to identify the scope and impact of a failure. The BR design uses a Containment Region to identify the resources affected by an incident. The Containment Region is initially formed with a fairly tight restriction on the scope of impact, but is expanded on receiving errors related to the first incident. The impact and scope of the failure is evaluated by traversing the resource relationships, evaluating information on BR specific resource pairing information, and determining most current state of the resources impacted.
Various types of preparatory and recovery processes are formulated and in some cases, optionally initiated. Workflows used by BR are dynamically generated based on, for instance, customer requirements for RTO goal, based on actual scope of failure, and based on any configuration settings customers have set for the BR system.
A workflow includes one or more operations to be performed, such as Start CICS, etc. Each operation takes time to execute and this amount of time is learned based on execution of the workflows, based on historical data in the observation log or from customer specification of execution time for operations. The workflows formalize, in a machine readable, machine editable form, the operations to be performed.
In one example, the processes are generated into Business Process Execution Language (BPEL) compliant workflows with activities that are operations on IT resources or specified manual, human activities. For example, BRM automatically generates the workflows in BPEL. This automatic generation includes invoking routines to insert activities to build the workflow, or forming the activities and building the XML (Extensible Mark-Up Language). Since these workflows are BPEL standard compliant, they can be integrated with other BPEL defined workflows which may incorporate manual activities performed by the operations staff. These BR related workflows are categorized as follows, in one example:
Since the set of BR actions described above modify existing IT environments, visibility to the actions that are taken by BR prior to the actual execution is provided. To gain trust in the decisions and recommendations produced by BR, the BR System can run in ‘advisory mode’. As part of advisory mode, the possible actions that would be taken are constructed into a workflow, similar to what would be done to actually execute the processes. The workflows are then made visible through standard workflow authoring tooling for customers to inspect or modify. Examples of BPEL tooling include:
BR tooling spans the availability management lifecycle from definition of business objectives, IT resource selection, availability policy authoring and deployment, development and deployment of runtime monitors, etc. In one example, support for the following is captured in the tooling environment for the BR system:
The policy lifecycle for BR goal policies, such as RTO goals, includes, for example:
One of the points in determining operational state of a Recovery Segment is that this design allows for customers to configure a definition of specific ‘aggregated’ states, using properties of individual IT resources. A Recovery Segment is an availability management context, in one example, which may include a diverse set of IT resources.
The customer may provide the rules logic used within the Recovery Segment to consume the relevant IT resource properties and determine the overall state of the RS (available, degraded and unavailable, etc). The customer can develop and deploy these rules as part of the Recovery Segment availability policy. For example, if there is a database included in the Recovery Segment, along with the supporting operating system, storage, and network resources, a customer may configure one set of rules that requires that the database must have completed the recovery of in-flight work in order to consider the overall Recovery Segment available. As another example, customers may choose to configure a definition of availability based on transaction rate metrics for a database, so that if the rate falls below some value, the RS is considered unavailable or degraded, and evaluation of ‘failure’ impact will be triggered within the BR system. Using these configurations, customers can tailor both the definitions of availability, as well as the rapidity with which problems are detected, since any IT resource property can be used as input to the aggregation, not just the operational state of IT resources.
Failures occurring during sequences of operations executed within a BPEL compliant process workflow are intended to be handled through use of BPEL declared compensation actions, associated with the workflow activities that took a failure. The BR System creates associated “undo” workflows that are then submitted to compensate, and reset the environment to a stable state, based on where in the workflow the failure occurred.
The following set of customer values, as examples, are derived from the BR system functions described above, listed here with supporting technologies from the BR system:
Management of the IT environment is adaptively performed, as described herein and in a U.S. patent application “Adaptive Business Resiliency Computer System for Information Technology Environments,” (POU920070364US1), Bobak et al., co-filed herewith, which is hereby incorporated herein by reference in its entirety.
Many different sequences of activities can be undertaken in creating a BR environment. The following represents one possible sequence; however, many other sequences are possible. This sequence is provided merely to facilitate an understanding of a BR system and one or more aspects of the present invention. This sequence is not meant to be limiting in any way. In the following description, reference is made to various U.S. patent applications, which are co-filed herewith.
On receiving the BR and related product offerings, an installation process is undertaken. Subsequent to installation of the products, a BR administrator may define the configuration for BR manager instances with the aid of BRM configuration templates.
Having defined the BRM configuration a next step could be to define Recovery Segments as described in “Recovery Segments for Computer Business Applications,” (POU920070108US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Definition of a RS may use a representation of resources in a topology graph as described in “Use of Graphs in Managing Computing Environments,” (POU920070112US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
It is expected that customers will enable BR operation in “observation” mode for a period of time to gather information regarding key metrics and operation execution duration associated with resources in a RS.
At some point, sufficient observation data will have been gathered or a customer may have sufficient knowledge of the environment to be managed by BR. A series of activities may then be undertaken to prepare the RS for availability management by BR. As one example, the following steps may be performed iteratively.
A set of functionally equivalent resources may be defined as described herein, in accordance with one or more aspects of the present invention.
Specification of the availability state for individual resources, redundancy groups and Recovery Segments may be performed as described in “Use of Multi-Level State Assessment in Computer Business Environments,” (POU920070114US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Representations for the IT environment in which BR is to operate may be created from historical information captured during observation mode, as described in “Computer Pattern System Environment Supporting Business Resiliency,” (POU920070107US1), Bobak et al., which is hereby incorporated herein by reference in its entirety. These definitions provide the context for understanding how long it takes to perform operations which change the configuration—especially during recovery periods.
Information on relationships between resources may be specified based on recommended best practices—expressed in templates—or based on customer knowledge of their IT environment as described in “Conditional Computer Runtime Control of an Information Technology Environment Based on Pairing Constructs,” (POU920070110US1), Bobak et al., which is hereby incorporated herein by reference in its entirety. Pairing processing provides the mechanism for reflecting required or desired order of execution for operations, the impact of state change for one resource on another, the effect execution of an operation is expected to have on a resource state, desire to have one subsystem located on the same system as another and the effect an operation has on preparing the environment for availability management.
With preliminary definitions in place, a next activity of the BR administrator might be to define the goals for availability of the business application represented by a Recovery Segment as described in “Programmatic Validation in an Information Technology Environment,” (POU920070111US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Managing the IT environment to meet availability goals includes having the BR system prioritize internal operations. The mechanism utilized to achieve the prioritization is described in “Serialization in Computer Management,” (POU920070105US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Multiple operations are performed to prepare an IT environment to meet a business application's availability goal or to perform recovery when a failure occurs. The BR system creates workflows to achieve the required or desired ordering of operations, as described in “Dynamic Generation of processes in Computing Environments,” (POU920070123US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
A next activity in achieving a BR environment might be execution of the ordered set of operations used to prepare the IT environment, as described in “Dynamic Selection of Actions in an Information Technology Environment,” (POU920070117US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Management by BR to achieve availability goals may be initiated, which may initiate or continue monitoring of resources to detect changes in their operational state, as described in “Real-Time Information Technology Environments,” (POU920070120US1), Bobak et al., which is hereby incorporated herein by reference in its entirety. Monitoring of resources may have already been initiated as a result of “observation” mode processing.
Changes in resource or redundancy group state may result in impacting the availability of a business application represented by a Recovery Segment. Analysis of the environment following an error is performed. The analysis allows sufficient time for related errors to be reported, insures gathering of resource state completes in a timely manner and insures sufficient time is provided for building and executing the recovery operations—all within the recovery time goal, as described in “Management Based on Computer Dynamically Adjusted Discrete Phases of Event Correlation,” (POU920070119US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
A mechanism is provided for determining if events impacting the availability of the IT environment are related, and if so, aggregating the failures to optimally scope the outage, as described in “Management of Computer Events in a Computer Environment,” (POU920070118US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Ideally, current resource state can be gathered after scoping of a failure. However, provisions are made to insure management to the availability goal is achievable in the presence of non-responsive components in the IT environment, as described in “Managing the Computer Collection of Information in an Information Technology Environment,” (POU920070121US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
With the outage scoped and current resource state evaluated, the BR environment can formulate an optimized recovery set of operations to meet the availability goal, as described in “Defining a Computer Recovery Process that Matches the Scope of Outage,” (POU920070124US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Formulation of a recovery plan is to uphold customer specification regarding the impact recovery operations can have between different business applications, as described in “Managing Execution Within a Computing Environment,” (POU920070115US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Varying levels of recovery capability exist with resources used to support a business application. Some resources possess the ability to perform detailed recovery actions while others do not. For resources capable of performing recovery operations, the BR system provides for delegation of recovery if the resource is not shared by two or more business applications, as described in “Conditional Actions Based on Runtime Conditions of a Computer System Environment,” (POU920070116US1), Bobak et al., which is hereby incorporated herein by reference in its entirety.
Having evaluated the outage and formulated a set of recovery operations, the BR system resumes monitoring for subsequent changes to the IT environment.
In support of mainline BR system operation, there are a number of activities including, for instance:
In order to build a BR environment that meets recovery time objectives, IT configurations within a customer's location are to be characterized and knowledge about the duration of execution for recovery time operations within those configurations is to be gained. IT configurations and the durations for operation execution vary by time, constituent resources, quantity and quality of application invocations, as examples. Customer environments vary widely in configuration of IT resources in support of business applications. Understanding the customer environment and the duration of operations within those environments aids in insuring a Recovery Time Objective is achievable and in building workflows to alter the customer configuration of IT resources in advance of a failure and/or when a failure occurs.
A characterization of IT configurations within a customer location is built by having knowledge of the key recovery time characteristics for individual resources (i.e., the resources that are part of the IT configuration being managed; also referred to as managed resources). Utilizing the representation for a resource, a set of key recovery time objective (RTO) metrics are specified by the resource owner. During ongoing operations, the BR manager gathers values for these key RTO metrics and gathers timings for the operations that are used to alter the configuration. It is expected that customers will run the BR function in “observation” mode prior to having provided a BR policy for availability management or other management. While executing in “observation” mode, the BR manager periodically gathers RTO metrics and operation execution durations from resource representations. The key RTO metrics properties, associated values and operation execution times are recorded in an Observation log for later analysis through tooling. Key RTO metrics and operation execution timings continue to be gathered during active BR policy management in order to maintain currency and iteratively refine data used to characterize customer IT configurations and operation timings within those configurations.
Examples of RTO properties and value range information by resource type are provided in the below table. It will be apparent to those skilled in the art that additional, less, and/or different resource types, properties and/or value ranges may be provided.
A specific example of key RTO properties for a z/OS® image is depicted in
The z/OS® image has a set of RTO metrics associated therewith, as described above. Other resources may also have its own set of metrics. An example of this is depicted in
Further, in one example, the RTO properties from each of the resources that are part of the Recovery Segment for App A have been gathered by BR and formed into an “observation” for recording to the Observation log, as depicted at 850.
Resources have varying degrees of functionality to support RTO goal policy. Such capacity is evaluated by BR, and expressed in resource property RTOGoalCapability in the BRMD entry for the resource. Two options for BR to receive information operation execution timings are: use of historical data or use of explicitly customer configured data. If BR relies on historical data to make recovery time projections, then before a statistically meaningful set of data is collected, this resource is not capable of supporting goal policy. A mix of resources can appear in a given RS—some have a set of observations that allow classification of the operation execution times, and others are explicitly configured by the customer.
Calculation of projected recovery time can be accomplished in two ways, depending on customer choice: use of historical observations or use of customers input timings. The following is an example of values for the RTOGoalCapability metadata that is found in the BRMD entry for the resource that indicates this choice:
If the customer is in observation mode, then historical information is captured, regardless of whether the customer has indicated use of explicitly input timings or use of historical information.
The administrator can alter, on a resource basis, which set of timings BR is to use. The default is to use historical observations. In particular, a change source of resource timing logic is provided that alters the source that BR uses to retrieve resource timings. The two options for retrieving timings are from observed histories or explicitly from admin defined times for operation execution. The default uses information from the observed histories, gathered from periodic polls. If the customer defines times explicitly, the customer can direct BR to use those times for a given resource. If activated, observation mode continues and captures information, as well as running averages, and standard deviations. The impact to this logic is to alter the source of information for policy validation and formulation of recovery plan.
With respect to the historical observations, there may be a statistically meaningful set of observations to verify. The sample size should be large enough so that a time range for each operation execution can be calculated, with a sufficient confidence interval. The acceptable number of observations to qualify as statistically meaningful, and the desired confidence interval are customer configurable using BR UI, but provided as defaults in the BRMD entry for the resource. The default confidence interval is 95%, in one example.
There are metrics from a resource that are employed by BR to enable and perform goal management. These include, for instance:
There is also a set of information about the resource that is employed—this information is provided as defaults in the BRMD entry for the resource, but provided to the BR team in the form of best practices information/defaults by the domain owners:
In addition to the resources defined herein as part of the IT configuration that is managed, there are other resources, referred to herein as assessed resources. Assessed resources are present primarily to provide observation data for PSE formation, and to understand impact(s) on managed resources. They do not have a decomposed RTO associated with them nor are they acted on for availability by BR. Assessed resources have the following characteristics, as examples:
Similarly, there are likely scenarios where a resource exists in a customer environment that already has an alternative availability management solution, and does not require BR for its availability. However, since other resources that are managed by BR may be dependent on them, they are observed and assessed in order to collect observation data and understand their impacts on managed resources. Additionally, there may be resources that do not have alternative management solutions, but the customer simply does not want them managed by BR, but other managed resources are dependent upon them. They too are classified as assessed resources.
These assessed resources share many of the same characteristics of managed resources, such as, for example:
Finally, there are a few restrictions that BR imposes upon assessed resources, in this embodiment:
To facilitate the building of the customer's IT configuration, observations regarding the customer's environment are gathered and stored in an observation log. In particular, the observation log is used to store observations gathered during runtime in customer environments, where each observation is a collection of various data points. They are created for each of the Recovery Segments that are in “observation” mode. These observations are used for numerous runtime and administrative purposes in the BR environment. As examples the observations are used:
BR gathers observations during runtime when “observation mode” is enabled at the Recovery Segment level. There are two means for enabling observation mode, as examples:
The administrator may also disable observation mode for a Recovery Segment, which stops it from polling for data and creating subsequent observation records for insertion in the log. However, the accumulated observation log is not deleted. In one example, an RS remains in observation mode throughout its lifecycle. The UI displays the implications of disabling observation mode.
In BR, the observations that are collected by BR during runtime can be grouped into two categories, as examples:
A periodic poll observation is a point-in-time snapshot of the constituent resources in a Recovery Segment. Observation data points are collected for those resources in the Recovery Segment(s) which have associated BR management data for any of the following reasons, as examples:
The full value of these observations is derived for an RS when they include data that has been gathered for its constituent resources, plus the resources that those are dependent upon. In one embodiment, the administrator is not forced to include all dependent resources when defining a Recovery Segment, and even if that were the case, there is nothing that prevents them from deleting various dependent resources. When defining a Recovery Segment, the BR UI provides an option that allows the customer to display the dependency graph for those resources already in the Recovery Segment. This displays the topology from the seed node(s) in the Recovery Segment down to and including the dependent leaf nodes. The purpose of this capability is to give the customer the opportunity to display the dependent nodes and recommend that they be included in the Recovery Segment.
Preparatory and recovery workflows are built by the BR manager to achieve the customer requested RTO policy based on resource operations timings. During active policy monitoring by the BR manager, measurements of achieved time for operations are recorded in observations to the log and used to maintain the running statistical data on operation execution times. Observations written to the log may vary in the contained resource RTO metrics and operation execution timings.
Observations are also collected from any of the BPEL workflows created by BR in the customer's environment. There is a standard template that each BR BPEL workflow uses. As part of that template, observation data is captured at the start of, during, and at the completion of each workflow. Specifically, in one example, one observation is created at the end of the workflow with data accumulated from completion of each activity. This information is used to gather timings for workflow execution for use in creating subsequent workflows at time of failure.
In accordance with an aspect of the present invention, management of a customer's environment is facilitated by defining and employing Redundancy Groups. For instance, Redundancy Groups are used to optimize the reconfiguration of resources to meet a desired goal, such as an availability goal or other goal. Redundancy groups are actively used during runtime to influence what operations are chosen (e.g., during reconfiguration) and what targets are selected for those operations. Further details associated with Redundancy Groups are provided below.
A Redundancy Group (RG) is a set of functionally equivalent resources. These resources can be represented in multiple ways, including, for instance, through the use of standards, such as the Common Information Model (CIM) Standard from the Distributed Management Task Force (DMTF) (see, e.g., http://www.dmtf.org/home). The RG configures and captures the resource existence, and relationship to other resource members. The state of the resource is used to evaluate selection of a target resource from a RG, but membership is not removed automatically when a resource becomes unavailable. Resources can be added to or removed from a RG by the customer or dynamically, as examples. Automated update of resources can be established through definition of criteria for inclusion/exclusion.
Redundancy Groups are defined to be, for instance:
Redundancy Groups are created by the customer in one of two ways. The formation process can use a RG Definition Template or the customer can explicitly specify resource instances that can be used for functional equivalence. Once defined, these sets are programmatically managed for change, state of each member, and selection criteria for choosing target members. Definition of a RG does not include a minimum or maximum number of members. However, the members that are included are functionally equivalent resources.
The BR UI enforces three restrictions, as examples, on Redundancy Groups when they are created:
The Redundancy Group is implemented, in one example, as a DB2 table in the Business Resilience datastore that physically resides in the BR environment. That database is created at installation time. It is not associated with a particular resource and is not used to persist any resource properties. The typical access mechanism is via, for instance, JDBC calls from the BR UI client(s) and the BRM using JDBC type 4 drivers. One example of the physical model of a Redundancy Group is shown below.
REDUNDANCY_GROUP
RG_ID INTEGER
DISPLAY_NAME: VARCHAR(96)
ACTIVE_PREFERENCE: CHAR(1)
AGGREGATED_STATE: INTEGER
RESOURCE_STATE_RULE: VARCHAR(128)
TS_UPDATE: TIMESTAMP
The Redundancy_Group table is used to associate various other DB2 entries via foreign keys. For example, to find the resources within a given Redundancy Group, the RG_ID can be used to query the BRMD table. The Redundancy Group table includes the following fields, as examples:
One embodiment of the logic associated with creating (or updating) a RG is described with reference to
Referring to
The list of RSs associated with the selected BRM instance is displayed from which a selection is made via the UI, STEP 904. Further, the topology associated with the selected RS is displayed via the UI, STEP 906.
Likely candidate resources to be associated with the RG can be selected directly by the customer or selected based on templates applied to the topology, STEP 908. Resources which are selected for inclusion in the RG are validated by ensuring they are of the same type as other resources in the RG, INQUIRY 910. If a selected resource is not of the same type, an error is presented via the UI, as well as a resource list for change, STEP 912. Thereafter, processing continues at STEP 908.
Returning to INQUIRY 910, if the selected resources are of the same type, then a further determination is made as to whether the RG specification is complete, INQUIRY 914 (
Otherwise, when all additions to the RG have been selected, a set of relational table updates are performed. For instance, the BRRD table is updated to reflect relationships between the resource and the RG, STEP 916, and the RG table is updated with added resources, STEP 918. Further, the BRMD for each resource is updated to indicate its association with the RG, STEP 920. This concludes the define RG processing.
Examples of Redundancy Groups are depicted in
Changes to a Redundancy Group can be accomplished by explicitly adding or deleting resources from the RG. Interfaces may be used to add, delete, and alter the membership of resources within a RG. Resources can be members in multiple RGs, and change to one RG membership does not affect another RG membership. The explicit changes are processed to reflect the new configuration programmatically, and uses of the changed RG will pick up the new information, as long as there is not a recovery in process at the time the change is attempted.
Updates to RG membership follow the same flow as initial creation of an RG, as described with reference to
The RG membership can also be extended to change dynamically, based on monitoring for events in the environment that match specified filters. For example, if a server that matches a specific RG Template comes online, it can be considered and evaluated for automatic membership in one or more RGs. In an environment, there can be a mix of RGs that have automatic update of membership, and some that are required to be explicitly modified. The control over dynamically changeable RG and explicitly controlled RG is customizable.
The automatic membership is used, for instance, where there are a large number of members in a RG and where resources may be expected to be created and destroyed frequently. One example may be a pool of thousands of Windows® based webservers. (Windows® is a registered trademark of Microsoft Corporation, Redmond, Wash.)
When automatic membership is desired, there is a set of event conditions that is monitored in the environment to cause evaluation of a resource as a candidate member based on specified filters. Likewise, when these events report resource state change, there is an evaluation of the condition to determine whether any RG is to have members expelled due to the dynamic change capability.
Redundancy Groups can participate directly in pairings related to impact assessment or co-location requirements. For impact assessment pairings, RG can directly contribute to a RS-to-RG impact pairing rule. For co-location pairings, RG can directly participate in attract/repel type of co-locations with other resource specifications.
In addition to the pairings related to impact assessment and co-location, RG state can contribute to the set of conditions under which any of the pairing rules trigger. Since pairings are specified to be conditionally evaluated when certain environmental triggers exist, the RG state can be one of those environmental triggers.
Across the runtime environment, there are a number of cases where there is information related to pairings of resources and operations on resources that BR will use. The assessment of the information across these pairings is dynamic to the current environment, rather than statically defined to be true across each instance of a given pairing of resources. Determination of pairing information use is performed by BR based on changes to resource state and a set of trigger rules defined with the pairing. Further details relating to pairing are described in “Conditional Computer Runtime Control of an Information Technology Environment Based on Pairing Constructs,” (POU920070110US1), which is hereby incorporated herein by reference in its entirety.
There are different categories of state changes which can impact other resources in some way, and each is considered in composing an impact pairing. These include, for instance:
Redundancy Groups have a defined state that is directly correlated to the state of the constituent members of the RG. Each of the resources has an operational state, but the overall state of the grouping of the resources can be aggregated into a state for the RG, as further described below, as well as in “Use of Multi-Level State Assessment in Computer Business Environments,” (POU920070114US1), which is hereby incorporated herein by reference in its entirety.
One embodiment of the logic to define RG aggregated state is described with reference to
Referring to
Thereafter, a determination is made as to whether there are any resource to RG state pairings to handle, INQUIRY 1106. If there are resource to RG impact effects to be defined, the resource effecting the state of the RG is selected, STEP 1108. Properties and state of the resource are presented for selection by the BR administrator, STEP 1110.
Specification of which property and associated value or resource state and the effect on the RG state are defined by the BR administrator, resulting in a temporary pairing rule—BRRD table entry—definition, STEP 1112. Moreover, the property impacting the RG is indicated in the BRMD, STEP 1114, and processing continues at STEP 1106.
When RG state based on member state specifications are complete, INQUIRY 1106, temporary pairing rules are made permanent in the BRRD table and BRMD table, STEP 1116. This concludes processing.
Determining Overall Availability of RS from State of RG
The business application represented by the Recovery Segment can have a number of inputs that affect its availability or degradation. The collective state of the RG can contribute as a factor to determining overall RS/business application state. That is, the state for the RG can be used in determining overall state of the RS and can be used as input to determine target selection among RG or within a RG. In addition, the management of a RG as an entity that has dynamic characteristics, defined state, and expected change, allows for the selection techniques from a RG to adapt to the current operating environment, rather than using a fixed preference list for selection, as described herein.
Using RG as part of the impact assessment definitions allows for redundancy characteristics of an environment to contribute to the assessment of whether a business application that may be represented by a Recovery Segment is ‘available’ vs. ‘degraded’. In some cases, customer environments are functioning as expected, however the redundancy capability is at risk or lost. The loss of redundancy is not always programmatically detected, identified, captured, or recommended for action. Since the loss of redundancy can affect business application availability (whether or not the redundancy reduction/loss is detected), programmatic specification and dynamic evaluation of pairing information allows more time sensitive recoveries and reduces overall risk to the business application. The feature to allow RG participation in pairing definitions for Business Resiliency allows customers to define whether a RG contributes to the state of a business application, and if so, to what extent.
In Define RS Aggregated State, the BR administrator is presented the set of RG(s) associated with the resources forming the RS as potential candidates on which the state of the RS could be altered.
In performing monitoring of the environment, a periodic poll of resource state and property values is performed. The following processing may be introduced in support of RG state having an impact on RS state. In particular, one embodiment of the logic used to manage responses to polling for resources is described with reference to
Referring to
When all resources having a response have been evaluated, the saved list of potentially impacted RG(s) is used to determine RG state impact. For each RG potentially being impacted, STEP 1208, the RG state aggregation rule is accessed, STEP 1210. Using the impact pairings for the RG, saved values for resource states and values of properties, the RG state is reevaluated, STEP 1212. This evaluation process is accomplished, in one embodiment, by combining the values of the various properties specified in the aggregation rule, according to the mathematical expression given in the rule. For example, if a RG was defined having two member resources and, if a resource changed to an unavailable state, the RG aggregated state rule could specify the RG should be evaluated as degraded if either of the two member resources becomes unavailable. As another example, a RG could be defined with three members all of which must be available for the RG to be considered available. As an example, three CICS resources must be available for the RG to be available. Additionally, each CICS resource has a composed state which specifies that the CICS resource is to be considered degraded if it is not processing 100 transactions/sec. Should any of the three CICS regions surface an event indicating the transaction/sec property has a value less than 100, the CICS region would be evaluated as degraded resulting in the RG it is associated with also being evaluated as degraded.
For each RG having changed state, STEP 1214, an assessment of RG state impact on resources is made. The impact pairings reflecting RG/resource effect are selected, STEP 1216. For each resource potentially impacted by the RG state change, STEP 1218 (
In performing recovery processing and asynchronous collection of information from resources, a query of resource state and property values is performed. The following logic may be introduced in that processing to support RG state having impact on RS state. For example, one embodiment of the logic associated with updating a RG, as well as a RS, after response to a query, is described with reference to
Referring to
Further, a determination is made as to whether the BRMD entry for the resource has RGs that are not yet in the RG list to evaluate, INQUIRY 1310. If so, the RGs are added to the RG list to evaluate, STEP 1312. Next or if there are no RGs to be added, a determination is made as to whether this is the last resource in the list of resources in the response from the query, INQUIRY 1314. If this is not the last resource, the next resource is selected, STEP 1316, and the flow returns to STEP 1302 to continue processing until all resources in the list are evaluated.
When all the resources in the response from query are evaluated, INQUIRY 1314, the RG aggregated state is determined, starting at STEP 1320 (
Next, a determination is made as to whether this is the last RG in the list to be evaluated, INQUIRY 1326. If this is not the last RG in the list, the next RG in the list is selected, STEP 1328, and processing returns to STEP 1322. This continues until all the RGs are processed, and INQUIRY 1326 evaluates true for the last RG.
In the next sequence of steps, the state of any RS impacted by the altered RG states is evaluated. The first RG in the list is selected, STEP 1330. Then, any RS that lists the selected RG in the RS Failure Impact Pairing rules is saved into a RS list to evaluate, STEP 1332. Thereafter, the first RS in that list is selected, STEP 1334, and the RS aggregated state is recalculated from, for instance, the state aggregation rules, STEP 1336. The temporary RS state data is then updated, STEP 1338. Next, an evaluation is made as to whether this is the last RS in the list for this RG, INQUIRY 1340. If not, the next RS is selected, STEP 1342, and processing cycles back to STEP 1336. However, if this is the last RS in the list for this RG, INQUIRY 1340, then a determination is made as to whether this is the last RG in the list, INQUIRY 1344. If not, the next RG is selected, STEP 1346, and processing cycles back to STEP 1332 to process the one or more Recovery Segments associated with the next RG.
When all the RGs in the list to evaluate have their associated RS assessed and updated, processing continues to STEPs 1348 and 1350 to update the RG aggregated state data from the temporary RG state data, and to update the RS aggregated state data from the temporary RS state data. As one example, this is performed using a short transaction.
Considerations for Co-Location when Starting Resources
Information about resource pairings is used to determine when a given resource is required to co-locate or required to not co-locate with another resource. The ordering information is used when an operation that requires or desires the move of a resource to a different hosting container is chosen as the recovery operation. Once such an operation is chosen, the co-location pairings for that resource are evaluated in choosing a target for the move. There are two basic options for co-location: attracts and repels.
These types of rules about co-location are expected to employ a conditional expression of when they should be exercised. BR uses the runtime state of the environment to assess whether a co-location requirement is to be enforced. One simple example is: a co-location requirement may exist between two resources, but only when the state of one resource is operational.
Selection from a RG when Starting Resources
During the process to evaluate co-location pairings, when the BR Manager selects a target resource to accommodate a move to a new hosting environment is required, the RG is evaluated to choose a viable candidate. Candidates are chosen, in one example, based on state of the individual resource being considered as a target, along with the overall set of co-location pairings for those resources which are to be recovered. For example, if 10 resources are to be moved to targets, the requirements of the set as a whole are evaluated and optimized, with respect to which resources have multiple targets, which have a more restricted list of alternate environments, etc.
One example of a technique for such a selection is described below. One input includes an operations list where each entry is a pair of resource and resource operations specifications. A second input determines if the selection is of a computer system on which to start an operating system (OS) or of an operating system on which to start a subsystem (e.g., APP, such as DB2 or CICS). The routine utilizes co-location pairings and RG definitions retrieved from the BRRD table and the RG table. For co-location pairings, there may exist, for example:
In the above example, CICS and DB2 are two examples of subsystems. However, other subsystems or applications may be employed.
One embodiment of the logic associated with finding a target is described with reference to
Referring initially to
For building a target candidate list of computer systems, pairings are selected from the BRRD in three sets of steps. In the first set of steps, processing cycles through the input list of resources until all have been evaluated, STEP 1401. Initially, the three target candidate lists are set to null, STEP 1402. Then, a first set of target candidate resources is created by selecting BRRD rows for which there exist a co-locate, attracts pairing identifying the input resource as the first resource and the computer system resource type as the second pairing component, STEP 1403. For each BRRD row returned, STEP 1404, the associated pairing is evaluated, STEP 1405. For those pairings which are currently valid, the computer system returned as part of the BRRD row is unioned with list “set1”, STEP 1406.
A second set of target candidate resources is created by selecting BRRD rows for which there exist a co-locate, attracts pairing identifying a computer system resource type as the first pairing component and the input resource as the second pairing component, STEP 1408 (
A third set of target candidate resources is created by selecting BRRD rows for which there exist a co-locate, attracts pairing identifying the input resource as the first resource and a computer system RG resource type as the second pairing component, STEP 1412. For each BRRD row returned, STEP 1413, the associated pairing is evaluated, STEP 1414. For those pairings which are currently valid, the computer system(s) returned as part of the RG are unioned with list “set3”, STEP 1415 (
When all three sources of target candidates have been evaluated, a composite target_candidate set is formed from the union of the three sources, STEP 1416 (
Returning to INQUIRY 1400, if a target for an OS is not requested, then a request is being made for a target for a subsystem start. Thus, a target candidate list of operating systems is built. To build a target candidate list of operating systems, each input resource is evaluated, STEP 1417 (
A second set of target candidate resources is created by selecting BRRD rows for which there exist a co-locate, attracts pairing identifying an operating system resource type as the first pairing component and the input resource as the second pairing component, STEP 1423 (
A third set of target candidate resources is created by selecting BRRD rows for which there exist a co-locate, attracts pairing identifying the input resource as the first resource and an operating system RG resource type as the second pairing component, STEP 1427. For each BRRD row returned, STEP 1428, the pairing is evaluated, INQUIRY 1429. For those pairings which are currently valid, the operating system resource(s) returned as part of the RG are unioned with list “set3”, STEP 1430.
When all three sources of target candidates have been evaluated, a composite target_candidate set is formed from the union of the three sources, STEP 1431 (
Repel processing occurs in two phases. In a first phase, a list of operating system(s) which repel the operating system for which a target is required or a list of subsystems which repel the subsystem for which a target is required is created. From the repel list, if there is a target assigned to the operating system or subsystem which repels the resource requiring a target, the assigned target of the repelling resource is removed from the target candidate list for the resource for which a start command target is being assigned.
At INQUIRY 1432, target candidates are removed from the list based on co-locate repel pairings. Initially, a determination is made as to whether a target for an operating system start is being made, INQUIRY 1432. If the target for an operating system start is being requested, then a repel list of operating systems is to be built.
For building a repel list of computer systems, pairings are selected from the BRRD in three steps. Processing cycles through the input list of resources until all have been evaluated, STEP 1433. Initially, set1, set2 and set3 are initialized to null, STEP 1434, and then a first set of repel resources is created by selecting BRRD rows for which there exist a co-locate, repels pairing identifying the input resource as the first resource and operating system resource type as the second pairing component, STEP 1435. For each BRRD row returned, STEP 1436, the associated pairing is evaluated, STEP 1437. For those pairings which are currently valid, the operating system returned as part of the BRRD row is unioned with list “set1”, STEP 1438.
A second set of repels resources is created by selecting BRRD rows for which there exist a co-locate, repels pairing identifying an operating system resource type as the first pairing component and the input resource as the second pairing component, STEP 1439 (
A third set of repels resources is created by selecting BRRD rows for which there exist a co-locate, repels pairing identifying the input resource as the first resource and an operating system RG resource type as the second pairing component, STEP 1443. For each BRRD row returned, STEP 1444, the associated pairing is evaluated, INQUIRY 1445. For those pairings which are currently valid, the operating system(s) returned as part of the RG are unioned with list “set3”, STEP 1446.
When all three sources of repel candidates have been evaluated, a composite repel_candidate set is formed from the union of the three sources, STEP 1447 (
Returning to INQUIRY 1432 (
A second set of repels resources is created by selecting BRRD rows for which there exist a co-locate, repels pairing identifying a DB2 or CICS resource type as the first pairing component and the input resource as the second pairing component, STEP 1454 (
A third set of repels resources is created by selecting BRRD rows for which there exist a co-locate, repels pairing identifying the input resource as the first resource and a DB2 or CICS RG resource type as the second pairing component, STEP 1458. For each BRRD row returned, STEP 1459, the associated pairing is evaluated, INQUIRY 1460. For those pairings which are currently valid, the DB2 or CICS resource(s) returned as part of the RG are unioned with list “set3”, STEP 1461.
When all three sources of repel candidates have been evaluated, a composite repel_candidate set is formed from the union of the three sources, STEP 1462 (
When each resource in the input list is processed, STEP 1433 (
For operating system type resources, INQUIRY 1464, any computer system image on the same CEC as a repelled operating system is to be removed from the target_candidate list. Determination of the computer system to CEC association begins by selecting each computer system in the target_candidate list, STEP 1465. The BRMD row is retrieved, STEP 1466, from which the associated CEC is extracted and saved with the target_candidate list entry, STEP 1467, for the associated computer system.
For each resource in the repel_candidate list of the resource, STEP 1468, the associated BRMD entry is retrieved, STEP 1469. If the repelled resource does not have an assigned target, INQUIRY 1470, the next repelled resource is processed. However, if the repelled resource has a target, a determination is made as to whether operating system resources are being assigned a target computer system, STEP 1471. If so, all target_candidate list entries with the same CEC as the CEC assigned to the repelled operating system instance are removed as candidates, STEP 1472.
Returning to INQUIRY 1471, for subsystems (e.g., CICS or DB2) having a repelled resource with an assigned target, INQUIRY 1470, that target is removed, if it exists, from the target_candidate list of the resource being processed, STEP 1473.
If a candidate target is removed resulting in no viable target resources, INQUIRY 1474, an error is indicated and the routine exited, in this example.
In the next phase of processing, potential targets which are not operational are removed from the target_candidate list of each resource. Initially, a composite of potential targets for all resources is formed, STEP 1484 (
If the resource type of “targets” is computer system, INQUIRY 1487, a determination is made as to whether the computer system is operational and available (having no associated operating system), INQUIRY 1488. If the computer system is not operational or not available (has an associated operating system), it is removed from all target_candidate sets for all resources, STEP 1489. If any target_candidate set becomes null as a result, INQUIRY 1490, an error response is generated and processing exits, in this example.
Returning to INQIURIES 1488 and 1490, if INQUIRY 1488 evaluates as true or INQUIRY 1490 evaluates as false, processing continues with STEP 1485.
Returning to INQUIRY 1487, if the resource type of “targets” is an operating system, a determination is made if the operating system is operational and available, INQUIRY 1491 (
However, if the operating system is operational and available, INQUIRY 1491, or if the target candidate list is not null, INQUIRY 1493, processing continues with STEP 1485 (
When all non viable targets have been removed, processing continues by enforcing co-locate attracts pairings between subsystems and between operating systems. Making an assignment for a target utilizes a common routine, “assign1”, described below. In performing the assignment of a target for a resource operation through “assign1”, the environment may be changed due to co-location pairings. The “assign1” routine operates with this routine to enforce co-locate pairings ensuring that resources requiring a target that have any attracts relationship, directly or implied by a chain of attracts relationships, are targeted to the same resource. When “assign1” completes the association of a target with a resource operation, related co-locate repels relationships are enforced by removing the target from any target_candidate set of a resource identified in a co-locate repels pairing.
Processing continues with processing of attracts pairings, an example of which is described with reference to
A second attracts set is selected from the BRRD using operating system type resource, co-locate attracts and the resource, STEP 1507 (
A third attracts set is selected from the BRRD using the resource, co-locate attracts and operating system RG type, STEP 1511. For each BRRD row returned, STEP 1512, the associated pairing is evaluated, INQUIRY 1513. For those pairings which are currently valid, the operating system members of the RG are unioned with list “set3”, STEP 1514.
The attract set, “attrset” for the resource is formed from the union of “set1”, “set2” and “set3”, STEP 1515.
Returning to INQUIRY 1502, if the resource for which a target is requested is not an operating system, processing continues with INQUIRY 1516 (
A second attracts set is selected from the BRRD using DB2 or CICS resource type, co-locate attracts and the resource, STEP 1521. For each BRRD row returned, STEP 1522, the associated pairing is evaluated, INQUIRY 1523 (
A third attracts set is selected from the BRRD using the resource, co-locate attracts and DB2 or CICS RG type, STEP 1525 (
The attract set, “attrset”, for the resource is formed from the union of “set1”, “set2” and “set3”, STEP 1529.
When the “attrset” for each resource has been built, each resource with a non-null attrset is processed, STEP 1530 (
For each root of the graph, STEP 1532, and for each resource in the graph root, STEP 1533, the BRMD row for the resource is retrieved, STEP 1534. If the resource has an assigned target, INQUIRY 1535, a determination is made as to whether the processing is of operating system type resources, INQUIRY 1536. If it is not for operating system type resources, but, instead, for subsystem type resources (e.g., CICS or DB2), INQUIRY 1536, and the assigned target is in the target_candidate list of the resource requiring a target for an operation, INQUIRY 1537, the “assign1” routine is invoked to make the assignment, STEP 1538, as described below. Otherwise, an error is indicated and processing exits, in one example.
Returning to INQUIRY 1536, if operating system type resources are being assigned a target, the target_candidate list is searched for any computer system having the same associated CEC, INQUIRY 1539. If no computer system candidate on the same CEC exists, an error is generated and processing exits, in one example.
For each computer system that is a candidate target and is on the same CEC as the operating system with an assigned CEC with a co-locate attracts pairing, STEP 1540, the BRMD of the target computer system is retrieved, STEP 1541. From the BRMD, the RS(s) associated with the computer system are determined, STEP 1542. From the set of PSE(s) associated with the RS(s), operation execution timings are extracted reflecting the time required to start this operating system on the potential target computer system. Operation timings are taken from PSE(s) which match the current date/time interval for measured or customer specified time required to start the operating system on the computer system, STEP 1543. When all potential computer system candidates have been evaluated for operation execution time, a target is selected having the smallest operation execution time, STEP 1544, and the “assign1” routine is invoked, STEP 1538.
In this example, techniques strongly enforce co-locate attracts pairings. If there exists any assigned target in the chain of co-locate attracts pairings, all related resources are targeted to the same resource. An extension to support co-locate attracts pairings, which is advisory and not mandatory, could be made. In doing so, processing would continue if an assigned target is not part of the target_candidate list for the resource. As an example, any available and operational target could be selected as a second choice.
Remaining is a set of resources requiring a target for an operation for which there exists some viable target and for which there exists no unenforced co-locate attracts and/or repels pairings. Processing continues by evaluating each root of the graph to assign a target, STEP 1545 (
As before, this particular embodiment of the technique enforces mandatory co-locate attracts pairings. A change in this technique to support advisory co-locate attracts pairings could be made by continuing if the intersect of target candidates is null. An alternative could chose to target the operation for the resource to any of the entries in the target candidate list.
The assignment of a target for the resource operation is selected from the intersect list of viable candidates by determining, for instance, which target has the smallest operation execution duration time for the set of resources requiring a target. For each target in the intersect list, STEP 1548, and for each resource requiring a target that is part of the graph root, STEP 1549, operation execution time data is retrieved. The BRMD row for the resource is read, STEP 1550, in order to locate the RS(s) this resource is associated with, STEP 1551. From operation execution timing for each PSE this resource is currently associated with, an average operation execution time is formed, STEP 1552. The average operation execution time for this resource is added to the total time for all resource operations to be assigned a target, STEP 1553, and saved with the target for later comparison.
When all potential targets have been evaluated for total time to process all operations requiring a target that are part of an attract set, a target is selected having the smallest total operation execution time, STEP 1554, and the “assign1” routine is invoked, STEP 1555. Processing continues at STEP 1545 for each root of the graph. When all roots have been processed, the flow continues at STEP 1556 (
For the remaining resource operation target assignments, the target which can satisfy the fewest requests is assigned first. Processing loops until all remaining resource operations requiring a target are assigned, STEP 1556. A target_list is built as the union of the remaining target_candidate lists for resource operations requiring a target assignment, STEP 1557. For each entry in the target_list, a count of the number of target_candidate lists in which it appears is made, STEP 1558. The target_list entry having the smallest count is selected, STEP 1559. The first resource operation having the selected target in its associated target_candidate list, STEP 1560, is assigned a resource operation target via assign1, STEP 1561.
The assign1 routine makes the resource operation target assignment, removes the resource operation from the list requiring assignment, makes assignments for any other resource requiring a target which has attracts co-locate pairing and removes the assigned target from target_candidate lists of resources for which there exists a repel co-locate pairing. If removing a target results in a null target_candidate list, an error is set and the routine exits, in one example. One embodiment of the logic for assigning a target is described with reference to
Referring to
Moreover, if the resource being assigned a target is other than an operating system (e.g., a subsystem), INQUIRY 1600, processing continues at STEP 1606, in which the resource is removed from the resource operation target list.
After removing the resource, the flow continues at STEP 1608 to process the repel_candidate lists. At STEP 1608, for all other repel_candidate lists (other than from the resource being assigned a target), if the resource being assigned a target appears in the list, INQUIRY 1610, the assigned target is removed from the target_candidate list, STEP 1612. Subsequent processing at the end of “assign1” will check to see if any target_candidate list became null. Moreover, if an operating system is being assigned a target computer system, INQUIRY 1614, the computer systems associated with the same CEC as the repelled operating system are removed from the target_candidate list, STEP 1616, and processing continues at STEP 1608.
Moreover, if the resource is not in the list, INQUIRY 1610, or is not an operating system, INQUIRY 1614, processing continues at STEP 1608.
Subsequent to processing the other repel_candidate lists, processing continues at STEP 1618. For each root of the graph built during formation of the “attrset” lists, STEP 1618, and for each resource in a root of the graph, STEP 1620, an assessment is made regarding the presence of a resource operation requiring a target, INQUIRY 1622 (
A check is made to determine if an operating system is being assigned a computer system as a target, INQUIRY 1624 (
Since a target assignment is being made due to “attrset” built from co-location expressions, each repelled resource is to have the target removed from it's target_candidate list. For each resource in the repel_candidate list of the resource being assigned a target, STEP 1628, if the resource being assigned a target appears in the list, INQUIRY 1630, the assigned target is removed from the target_candidate list of the repelled resource, STEP 1632. Further, if an operating system is assigned a computer system, INQUIRY 1634, the computer systems having the same associated CEC as the repelled operating system are removed from the target_candidate list, STEP 1636, and processing returns to STEP 1628. If, however, the resource does not appear in the list, INQUIRY 1630, or a subsystem is being assigned a target, INQUIRY 1634, processing returns to STEP 1628.
When all repel_candidate lists have been processed, the resource operation which is part of the “attrset” is assigned a target. Thus, processing continues at INQUIRY 1638, in which a determination is made as to whether an operating system is being assigned a target computer system. If so, and no target computer system associated with the same CEC is in the target_candidate list, INQUIRY 1644, an error is indicated and processing ends, in this example. Otherwise, for each computer system on the same CEC, STEP 1646, the BRMD of the target computer system is retrieved, STEP 1648. From the BRMD, the set of RS(s) associated with the computer system are determined, STEP 1650. Further, operation execution time averages for the required date/time range are formed, STEP 1652. In one example, this can be based on PSE(s) that match the requested date/time range. When all eligible target computer systems have been evaluated, INQUIRY 1646, the target having the smallest operation execution time is selected as the computer system target for the operating system, STEP 1654. Further, the target is removed from the list of operations requiring a target assignment, STEP 1656, and processing returns to STEP 1620 (
Returning to INQUIRY 1638 (
At STEP 1620, when all roots of the “attrset” graph have been processed, a determination is made regarding any target_candidate list(s) having become null, INQUIRY 1660 (
In the above selection logic, various examples of attracts and repels are provided. These are only examples. Additional, less and/or other examples may be provided. For instance, in another embodiment, an OS can be repelled from a particular computing system.
Selection from RG Based on Quality of Service Characteristics
Choice of a resource within the RG can also be prioritized based on performance and other quality of service characteristics for best choice from among the set of resources associated with the RG. For example, throughput, bandwidth, and response time criteria are three examples of criteria that may be used in further optimizing and extending the selection technique. Optimizing using additional quality of service characteristics in the selection criteria allows the RG to be even more dynamic in its ability to respond to changes in the environment.
In one example, processing is provided to delete an existing RG from the environment managed by the BRM. In this example, the flow finds related BRMD and BRRD entries that have to be cleaned up to keep referential integrity in the data (and enforced by DB2). This flow is initiated from the UI, and processed after verifying the delete request.
Described in detail above is the definition and use of Redundancy Groups in runtime management of business applications.
One or more aspects of the present invention can be included in an article of manufacture (e.g., one or more computer program products) having, for instance, computer usable media. The media has therein, for instance, computer readable program code means or logic (e.g., instructions, code, commands, etc.) to provide and facilitate the capabilities of the present invention. The article of manufacture can be included as a part of a computer system or sold separately.
One example of an article of manufacture or a computer program product incorporating one or more aspects of the present invention is described with reference to
A sequence of program instructions or a logical assembly of one or more interrelated modules defined by one or more computer readable program code means or logic direct the performance of one or more aspects of the present invention.
Advantageously, a capability is provided for facilitating active management of business applications during runtime. Redundancy groups, each of which include functional equivalent resources, are employed in the reconfiguration of resources associated with a business application to meet desired goals, such as availability goals or other goals of the application.
Although various embodiments are described above, these are only examples. For example, the processing environments described herein are only examples of environments that may incorporate and use a Redundancy Group and/or one or more other aspects of the present invention. Environments may include other types of processing units or servers or the components in each processing environment may be different than described herein. Each processing environment may include additional, less and/or different components than described herein. Further, the types of central processing units and/or operating systems or other types of components may be different than described herein. Again, these are only provided as examples.
Moreover, an environment may include an emulator (e.g., software or other emulation mechanisms), in which a particular architecture or subset thereof is emulated. In such an environment, one or more emulation functions of the emulator can implement one or more aspects of the present invention, even though a computer executing the emulator may have a different architecture than the capabilities being emulated. As one example, in emulation mode, the specific instruction or operation being emulated is decoded, and an appropriate emulation function is built to implement the individual instruction or operation.
In an emulation environment, a host computer includes, for instance, a memory to store instructions and data; an instruction fetch unit to obtain instructions from memory and to optionally, provide local buffering for the obtained instruction; an instruction decode unit to receive the instruction fetched and to determine the type of instructions that have been fetched; and an instruction execution unit to execute the instructions. Execution may include loading data into a register for memory; storing data back to memory from a register; or performing some type of arithmetic or logical operation, as determined by the decode unit. In one example, each unit is implemented in software. For instance, the operations being performed by the units are implemented as one or more subroutines within emulator software.
Further, a data processing system suitable for storing and/or executing program code is usable that includes at least one processor coupled directly or indirectly to memory elements through a system bus. The memory elements include, for instance, local memory employed during actual execution of the program code, bulk storage, and cache memory which provide temporary storage of at least some program code in order to reduce the number of times code must be retrieved from bulk storage during execution.
Input/Output or I/O devices (including, but not limited to, keyboards, displays, pointing devices, DASD, tape, CDs, DVDs, thumb drives and other memory media, etc.) can be coupled to the system either directly or through intervening I/O controllers. Network adapters may also be coupled to the system to enable the data processing system to become coupled to other data processing systems or remote printers or storage devices through intervening private or public networks. Modems, cable modems, and Ethernet cards are just a few of the available types of network adapters.
Further, although the environments described herein are related to the management of availability of a customer's environment, one or more aspects of the present invention may be used to manage aspects other than or in addition to availability. Further, one or more aspects of the present invention can be used in environments other than a business resiliency environment.
Yet further, many examples are provided herein, and these examples may be revised without departing from the spirit of the present invention. For example, in one embodiment, the description is described in terms of availability and recovery; however, other goals and/or objectives may be specified in lieu of or in addition thereto. Additionally, the resources may be other than IT resources. Further, in the tables described herein, there may be references to particular products offered by International Business Machines Corporation or other companies. These again are only offered as examples, and other products may also be used. Additionally, although tables and databases are described herein, any suitable data structure may be used. There are many other variations that can be included in the description described herein and all of these variations are considered a part of the claimed invention.
Further, for completeness in describing one example of an environment in which a RG may be utilized, certain components and/or information is described that is not needed for one or more aspects of the present invention. These are not meant to limit the aspects of the present invention in any way.
The terms “obtaining” used herein includes, but is not limited to, creating, defining, building, forming, having, receiving, being provided, retrieving, etc.
One or more aspects of the present invention can be provided, offered, deployed, managed, serviced, etc. by a service provider who offers management of customer environments. For instance, the service provider can create, maintain, support, etc. computer code and/or a computer infrastructure that performs one or more aspects of the present invention for one or more customers. In return, the service provider can receive payment from the customer under a subscription and/or fee agreement, as examples. Additionally or alternatively, the service provider can receive payment from the sale of advertising content to one or more third parties.
In one aspect of the present invention, an application can be deployed for performing one or more aspects of the present invention. As one example, the deploying of an application comprises providing computer infrastructure operable to perform one or more aspects of the present invention.
As a further aspect of the present invention, a computing infrastructure can be deployed comprising integrating computer readable code into a computing system, in which the code in combination with the computing system is capable of performing one or more aspects of the present invention.
As yet a further aspect of the present invention, a process for integrating computing infrastructure, comprising integrating computer readable code into a computer system may be provided. The computer system comprises a computer usable medium, in which the computer usable medium comprises one or more aspects of the present invention. The code in combination with the computer system is capable of performing one or more aspects of the present invention.
The capabilities of one or more aspects of the present invention can be implemented in software, firmware, hardware, or some combination thereof. At least one program storage device readable by a machine embodying at least one program of instructions executable by the machine to perform the capabilities of the present invention can be provided.
The flow diagrams depicted herein are just examples. There may be many variations to these diagrams or the steps (or operations) described therein without departing from the spirit of the invention. For instance, the steps may be performed in a differing order, or steps may be added, deleted, or modified. All of these variations are considered a part of the claimed invention.
Although embodiments have been depicted and described in detail herein, it will be apparent to those skilled in the relevant art that various modifications, additions, substitutions and the like can be made without departing from the spirit of the invention and these are therefore considered to be within the scope of the invention as defined in the following claims.
