Agents Administration - Tests
 

Configuration of EMCPvMeCtlTest

The storage controller is essentially a server that's responsible for performing a wide range of functions for the storage system. Each controller has an I/O path to communicate to the storage network or the directly-attached servers, an I/O path that communicates to the attached storage devices or shelves of devices, and a processor that handles the movement of data as well as other data-related functions, such as RAID and volume management. In the modern data center, the performance of the storage system can be directly impacted (and in many cases determined) by the speed and capabilities of the storage controller. If the controller or its processor is unable to meet the I/O processing demands of the infrastructure they support, then slowdowns will become a norm, and user complaints will become routine. Under such circumstances, IT administrators will seriously consider switching to alternative storage solutions with more robust controllers and high processing power. To avoid this eventuality, administrators need to keep checking on overall controller performance and processor usage from time to time, so that they can spot a potential I/O overload condition or a processing delay or a CPU contention before user experience is affected, and fine-tune cache usage, processor capacity, and/or the load-balancing algorithm of the controller to ensure peak performance of the storage system at all times. The EMCPvMeCtlTest helps administrators in this regard.

This test auto-discovers the controllers of the EMC PowerVault ME storage system, monitors the I/O processing ability of each controller, and reveals the following:

  • Is any controller hogging its CPU? If so, which one is it?

  • Which controller is slow in processing I/O requests? What type of requests are being serviced slowly by that controller - read requests or write requests?

  • How is the cache usage of the slow controller? Is the cache being utilized optimally, or are too many read-write requests serviced by direct disk accesses?

The answers to these questions indicate how healthy each controller is and provide pointers to right-size the processor and controller cache (if needed).

The default parameters associated with this test are:

  • The TEST PERIOD list box helps the user to decide how often this test needs to be executed.

  • In the HOST text box, specify the HOST for which this test is to be configured. Since the storage device is managed using the IP address of its storage controller, the same will be displayed as host. In case of a dual-controller configuration, the IP address of the primary controller will be displayed here.

  • Specify the port number at which the specified host listens in the PORT text box. By default, this is NULL.

  • By default, this test always connects to the Host to collect metrics. If the Host is unavailable, then the test will not be able to execute. This is because, the Additional Controller IP is set to none by default.

    If the monitored storage device has two controllers, then you can configure the test to connect to an alternate controller, if the host is unreachable. For this purpose, specify the IP address of the alternate controller in the Additional Controller IP text box.

  • In order to monitor a EMC PowerVault ME storage system, the eG agent has to be configured with the credentials of a user who has been assigned the Monitor role. Specify the login credentials of such a user in the USER and PASSWORD text boxes. To know how to create such a user, refer to Pre-requisites-for-monitoring-the-EMC PowerVault-ME-storage-system. Confirm the password by retyping it in CONFIRM PASSWORD text box.

  • The Management Controller of the EMC PowerVault ME storage system provides access for monitoring and management via the HTTP and HTTPS protocols for XML API request/response semantics. To enable the eG agent to access the management controller, invoke the XML API commands, and collect the required metrics, you need to specify the SERVICE PORT on the controller that listens for HTTP/HTTPS requests for XML API semantics. By default, this is port 80.

  • Specify the time duration for which this test should wait for a response from the storage system in the TIMEOUT text box. By default, this is 60 seconds.

  • By default, EMC PowerVault ME system is not SSL-enabled. This is why, SSL flag is set to False by default. If it is SSL-enabled, then change this flag to True.

  • If multiple components of the same component type are awaiting configuration, then an APPLY TO OTHER COMPONENTS button will appear in this page. Clicking on this button will allow you to apply the configuration to all/selected components of that type.

  • Once the necessary values have been provided, clicking on the UPDATE button will register the changes made.

When changing the configuration for specific servers, a “*” beside the text box corresponding to the parameter signifies that these values have to be manually configured by the user. The parameter values that require to be configured will typically be prefixed with a “$” or contain a series of “*”. A value of “none” in the parameter value indicates that the corresponding parameter value can be changed if required.