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1. Field of the Invention
This invention relates to storage network systems, and particularly to systems and methods for monitoring high-speed network traffic via simultaneously multiplexed data streams.
2. Description of Background
In storage network systems that have internalized high-speed fabrics, a high-speed switch is used to provide connectivity amongst individual servers and associated storage. In addition, such network storage systems can include multiple high-speed fabrics (1× and 4×). High-speed differential signaling is used to provide high bandwidth connections between a central serial attached SCSI (SAS) switch and other endpoints such as other switches or downstream or upstream storage components. SAS Switches can support multiple configurations, and several topologies, such as 16 external SAS ports, which can be “wide” or “narrow”. A wide port is comprised of multiple 1× links (e.g., PHYs) such as a 4×, 8×, 12×, etc., wide port.
In such systems, much of the storage area network (SAN) is internalized, wherein the server blades and the switch modules are coupled to one another via internal fabric. Such internalization can create problems that require access to pertinent data for problem detection, analysis and fault isolation. In some SAN systems, test equipment (e.g., a logic analyzer) can be inserted or onto a suspected high-speed interface such as the external fiber channel and capture pertinent data for problem resolution. However, when high-speed fabrics are internalized, it becomes difficult to access the fabric for troubleshooting problems. Although solutions, such as creating software trace events in microcode and directing error messages to a debug port, have been implemented, such solutions have shortcomings, including inaccurate detail of the failure, non real-time reporting of the failure, and resultant numerous iterations of adding a debug patch to isolate the problem. Other more invasive methods can include adding wires to a card to allow internal probing. This hardware-type approach is invasive to the system, limiting its analysis capability, and can cause potential corruption of the monitored data. In other instances, permanent electrical damage to the probed fabric circuitry can result. Although many of these approaches can be implemented in a controlled laboratory setting, these approaches are unsuitable for a customer environment. Therefore, there exists a need for systems and methods to troubles-hoot internalized high-speed fabric networks in a customer environment.
Exemplary embodiments include a switch module system, including a first switch module coupled to a first server chassis, a first data port disposed on the first switch module and a set of data links disposed on the first data port, each data link configurable to receive a normal data stream and a monitored data stream.
Additional embodiments include a computer-readable medium having computer-executable instructions for performing a method, including configuring a multi-chassis system configured to support a server and a switch module to run data streams for the server and over the switch module, detecting a data failure on at least one data link coupled to the switch module, determining a data stream rate on the data link and configuring the data link to support a normal data stream and a monitored data stream on the data link.
Further embodiments include a switch module data monitoring method, including configuring a multi-chassis system to run data streams over a switch module interconnecting the multi-chassis system, detecting a data failure on at least one data link coupled to the switch module, determining a data stream rate on the data link, the data stream rate being at least one of 3 Gbit/s and 6 Gbit/s and configuring the data link to support a normal data stream and a monitored data stream on the data link configured at a rate of 6 Gbit/s, wherein the normal data stream and the monitored data stream are time multiplexed as a single data stream on the data link.
Other systems, methods, and/or computer program products according to embodiments will be or become apparent to one with skill in the art upon review of the following drawings and detailed description. It is intended that all such additional systems, methods, and/or computer program products be included within this description, be within the scope of the present invention, and be protected by the accompanying claims.
As a result of the summarized invention, real-time tracing and troubleshooting of internal high speed fabric problems in a system configuration where all external SAS links are consumed running normal SAS I/O is achieved.
The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed 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:
The detailed description explains the preferred embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
Exemplary embodiments include multi-chassis network systems that implement time multiplexing of multiple SAS I/O streams to monitor I/O data. An external SAS port can be configured for multiplexing one I/O stream and one monitored (or “snooped”) stream on a shared SAS link (e.g., a PHY). In an exemplary implementation, a 6 Gbit/s link is used to run two 3 Gbit/s streams implementing time multiplexing. As such, one stream can be SAS I/O data running at 3 Gbit/s, while the second stream can be the data of interest to be traced, running at 3 Gbit/s,
The system 200 further includes a second chassis network 250, having a second switch module 255, having wide ports 260a, 260b, 260c, 260d and data links J, K, L, M, and coupled to the first switch module 220 via the external fabric 240. It is appreciated that the external fabric 240, which can be a fiber cable, Ethernet Cable, SCSI cable, etc., is the medium that couples the wide ports 230, 260, and or individual links E, F, G, H, J, K, L, M to one another. The second switch module 255 can be coupled to and in communication with other internal or external storage such as, but not limited to, a second network chassis, a switch bunch of disks (SBOD), etc. It is further appreciated that any number of additional chassis networks, or other storage network media can be coupled to and in communication with the first and second chassis networks 205, 250 either upstream or downstream.
In general, high-speed switch technology provides the ability to selectively and redundantly mirror high-speed traffic to ports (e.g., wide ports, individual data links, etc.) on the same switch. For example, one or more of the wide ports 230a, 230b, 230c, 230d (or individual data links E, F, G, H) on first switch module 220 can be configured to monitor the other wide ports 230a, 230b, 230c, 230d (or individual data links E, F, G, H) on the first switch module 220. Such use of the wide ports 230a, 230b, 230c, 230d and/or data links E, F, G, H is now described in accordance with exemplary embodiments. This monitoring feature is also known as “snooping”, that is, high-speed traffic in progress through, for example, the first switch module 220 can be “snooped” or monitored and then directed to yet another port on the first switch module 220, that is, the port being dedicated for snooping. It is appreciated that, in order to have a snooping port or link, the first switch module 220 has available ports or links for snooping. In the system 200 illustrated in
Referring still to
System 200 further includes the capability to connect an external computing device 290, such as a laptop computer to a debug port 291, 292 on the first and second switch modules 220, 255. The external computing device 290 can configure the ports 230a-230d, 260a-260d and data links E-H, J-M to support the different data rates 3 Gbit/s and 6 Gbit/s as well as port/link mapping as further discussed below.
It is appreciated that the external computing device 290 can include a process to configure the ports/links as needed. As such, in the example discussed in the preceding paragraph, if the wide port is already configured to and operating at 6 Gbit/s, then the external computing device 290 is used to configure (throttle) the links 275a-275d to run at the 3 Gbit/s rate. Furthermore, the external computing device is used to bypass the snooped data stream 280 from link A to link E, thereby bypassing the first switch module. As such, the multiplexed data stream 275a, 280 includes data from link A having passed through the first switch module 220, that is data stream 275a, and the data stream that has not passed through the first switch module, that is, snooped data stream 280, the aggregation of both links totaling the 6 Gbit/s link data rate. As discussed, these two data streams are time multiplexed and passed through links E, J and through the logic analyzer 270. It is therefore appreciated that the multiplexed data stream 275a, 280 can be used to analyze data faults as a result of passing through the first switch module 220. If there are differences in the data stream 275a, 280, then the user may conclude that there is a fault relating to the first switch module 220. If there is no difference between the data streams 275a, 280, then the user may conclude that the problem may be in one of the independent servers 215 of the chassis 210.
Referring still to
It is appreciated that the external computing device 290 can include a process to configure the ports/links as needed. As such, in the example discussed in the preceding paragraph, the external computing device 290 is used to configure the port 230a to run at the 6 Gbit/s rate. Furthermore, the external computing device is used to bypass the snooped data stream 280 from link A to link E, thereby bypassing the first switch module. As such, the multiplexed data stream 275a, 280 includes data from link A having passed through the first switch module 220, that is data stream 275a, and the data stream that has not passed through the first switch module, that is, snooped data stream 280.
As an example and referring still to
If it is determined that the failure path is running at 6 Gbit/s at step 420, then at step 445, the port is reconfigured to run single 3 Gbit/s stream 275a plus the snoop data stream 280, which, is also running at 3 Gbit/s. At step 435 the failure is captured on the logic analyzer 270 as discussed above. At step 440, the snoop data stream 280 is ignored by the subsequent switch module, which can be second switch module 255. It is appreciated that the method 400 continues as data faults and failures occur.
The capabilities of the present invention can be implemented in software, firmware, hardware or some combination thereof.
As one example, 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 embodied therein, for instance, computer readable program code means for providing and facilitating the capabilities of the present invention. The article of manufacture can be included as a part of a computer system or sold separately.
Additionally, at least one program storage device readable by a machine, tangibly 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.
As described above, embodiments can be embodied in the form of computer-implemented processes and apparatuses for practicing those processes. In exemplary embodiments, the invention is embodied in computer program code executed by one or more network elements. Embodiments include computer program code containing instructions embodied in tangible media, such as floppy diskettes, CD-ROMs, hard drives, or any other computer-readable storage medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. Embodiments include computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an apparatus for practicing the invention. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.