SRM

Some useful SRM advance settings

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Most of us who work with SRM will know that a success of an SRM (Vmware Site recovery manager) workflows is highly dependent on time a storage array takes to process SRA commands. While working with customers I have noticed that following advance settings are very handy in tuning the SRM timeout for letting it wait longer.

Storage Settings:

storage.commandTimeout:

The default value of this parameter is 300 seconds. This setting determines how long SRM waits for a command that was issued by the SRA to complete. It is sometimes necessary for SRM to wait a little longer for an SRA command to complete. Working with SRM in last few years I have noticed in most cases 900/1200 works the best.

Procedure to change storage settings 
  1. Click Sites in the Site Recovery Manager interface
  2. right-click the site on which to change settings
  3. Select Advanced Settings.
  4. Click storage.
  5. Modify the storage settings.

It is best to change the settings for both sites.

storageProvider settings

storageProvider.hostRescanRepeatCnt:

The default value of this parameter is 1. During a recovery plan or test recovery plan, the hosts on the recovery site have to perform a rescan to discover the recovered datastores. Some storage arrays require more time to present the recovered datastores and a second or third rescan is required to successfully pick up all the recovered datastores. In most cases I have seen 3 is good number of rescans to pick all the recovered datastores.

storageProvider.hostRescanTimeoutSec:

The default value of this parameter is 0 seconds. During a recovery plan or test recovery plan, it may be necessary to change this value to allow SRM to wait longer for a HBA rescan to complete on the recovery site. In most cases 300 is good number to keep for this value.

storageProvider.fixRecoveredDatastoreNames:

This option is disabled by default. During the execution of SRM recovery plan a re-signature operation is carried out on the recovered devices. This lead to the addition of a prefix like “snap-xxxxxxx” to the datastore name. Enabling this option renames the datastore to its original name.

storageProvider.resignatureFailureRetryCount:

The default value of this parameter is 0. During a recovery plan or test recovery plan, it may be necessary to change this value to allow SRM to retry a re-signature operation. In most cases keeping this value equal to the value of storageProvider.hostRescanRepeatCnt works the best

Procedure to change storageProvider settings
  1. Click Sites in the Site Recovery Manager interface
  2. Right-click the site on which to change settings
  3. Select Advanced Settings.
  4. Click storageProvider.
  5. Modify the storageProvider settings

It best to change the settings for both sites.