VSP Disk Adapters Test

A disk adapter controls the transfer of data between the drives and cache. If data is not being transferred successfully or if administrators experience slowness in data transfer, then it indicates that one of the disk adapters is not functioning or is being over-utilized leading to errors in data transmission. In order to maintain a smooth and error free data transmission, it is essential on the part of the administrators to monitor the usage of the disk adapters. The VSP Disk Adapters test helps administrators in this regard!

This test monitors the usage of each disk adapter, and reveals over-utilized adapters (if any).

Target of the test : A Hitachi VSP storage device

Agent deploying the test : A remote agent

Outputs of the test : One set of results for every disk adapter on the target Hitachi VSP device being monitored

Configurable parameters for the test
  1. TEST PERIOD - How often should the test be executed
  2. HOST - The host for which the test is to be configured.
  3. PORT - The port at which the device listens. By default, this is set to NULL.

  4. USERID and PASSWORD – To extract metrics from the target storage device, the eG agent should be configured with the credentials of a special user account, which is specifically created for use with the Java export utility. This user account should fulfill the following conditions:

    • Should not possess the ‘write’ permission;
    • Can be of any user type; however, to ensure that the eG agent collects statistics pertaining to all storage partitions, it is recommended that this user is of type storage administrator;

    Specify the credentials of such a user in the USERID and PASSWORD text boxes.

  5. CONFIRM PASSWORD - Confirm the password by retyping it here.
  6. TIMEOUT - Specify the duration (in seconds) within which the SNMP query executed by this test should time out in the TIMEOUT text box. The default is 3 seconds.
Measures made by the test:
Measurement Description Measurement Unit Interpretation

Disk adapter usage:

Indicates the percentage of time for which this disk adapter was in use.

Percent

A high value or a value close to 100% is indicative of excessive usage of the disk adapters. By comparing the value of this measure across adapters, you can accurately detect imbalances in load distribution, and rapidly identify the affected disk processors. To ensure that load is balanced, you might want to consider the following:

  • Install additional HDDs (hard disk drives) or DKAs, and then, using Volume Migration, migrate the high-write-usage volumes (especially sequential writes) to the new parity groups; or;

  • Use Volume Migration to migrate logical volumes from high-usage parity groups to low-usage parity groups;