Dell 36XX, 34XX, 38XX, 32XX Recovery Operations, Setting RAID Controller Module Operational Mode

physical disk-side channel out onto the loop and back again. Enough data is transferred to determine error conditions on the channel. If the test fails on any channel, this status is saved so that it can be returned if all other tests pass.

The write test initiates a write command as it would be sent over an I/O data path to the diagnostics region on a specified physical disk. This diagnostics region is then read and compared to a specific data pattern. If the write fails or the data compared is not correct, the RAID controller module is considered to be in error, and it is failed and placed offline.

For best results, run all three tests at initial installation. Also, run the tests any time you make changes to the storage array or to components connected to the storage array (such as hubs, switches, and host adapters).

A custom data pattern file called diagnosticsDataPattern.dpf is included on the Utility directory of the installation CD. You can modify this file, but the file must have the following properties to work correctly for the tests:

•The file values must be entered in hexadecimal format (00 to FF) with only one space between the values.

•The file must be no larger than 64 bytes in size. Smaller files can be used, but larger files can cause an error.

The test results contain a generic, overall status message and a set of specific test results. Each test result contains the following information:

•Test (read/write/data loopback)

•Port (read/write)

•Level (internal/external)

•Status (pass/fail)

Events are written to the MEL when diagnostics are started and when testing is completed. These events help you to evaluate whether diagnostics testing was successful or failed and the reason for the failure.

Recovery Operations

Recovery operations involve replacing failed RAID controller modules and physical disks, restoring data, and restoring the storage array to operation.

Setting RAID Controller Module Operational Mode

A RAID controller module has three operational modes:

•Online

•Offline

•Service

CAUTION: Placing a RAID controller module offline can cause loss of data.

Placing a RAID controller module online sets it to the Optimal state and makes it active and available for I/O operations. Placing a RAID controller module offline makes it unavailable for I/O operations and moves its disk groups to the other RAID controller module if failover protection is enabled.

Taking a RAID controller module offline can seriously impact data integrity and storage array operation.

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