Advanced - Fujitsu Eternus DX

Best Practices

• It is important not to perform any configurations on the ETERNUS Console while running snapshot operations in the CommCell Console.
• For SnapOPC snapshots, the SDV volume should be pre-paired with the source before performing snapshot operations.
• For EC (clone) snapshots, the destination volume should be pre-paired with the source before performing snapshot operations. After pre-pairing, the destination volume should not be left in a suspended state.

• In order to use a specific initiator for accessing snapshots during SnapProtect backup set the sSNAP_UseINITIATOR registry key to the desired initiator address.

FAQ

What are the target volume selection rules?

The target volume selection rules for Clone and Snap Snapshots are discussed below:

For Clone Snapshots

1. The first priority is given to pre-paired sessions in the following order:
   • If special name is set by the registry key ETERNUS_USE_VOLUME_LABEL, then pre-paired session with target volume having special name will be given preference. If no such pre-paired session found, any existing pre-paired session will be picked.
   • If the registry key ETERNUS_USE_VOLUME_LABEL is not set, pre-paired sessions with volumes named as iSnapR_<xyz> will be given preference. If no such pre-paired session found, any existing pre-paired session will be picked.
2. If pre-paired sessions are not available, preference is given to target volumes with a special name set by the registry key ETERNUS_USE_VOLUME_LABEL. If there are no suitable volumes with the special name, the backup job will fail. If there are more than one volumes with the special name, preference will be based on the source volume type. If source volume is a standard volume, preference will be given to standard volumes otherwise thin provisioning volume.
3. If no target volumes are available, a volume will be created using the specified destination pool.

For Snap Snapshots

1. The first priority is given to pre-paired sessions in the following order:
   • If special name is set by the registry key ETERNUS_USE_VOLUME_LABEL, then pre-paired session with target volume having special name will be given preference. If no such pre-paired session found, any existing pre-paired session will be picked.
   • If the registry key ETERNUS_USE_VOLUME_LABEL is not set, pre-paired sessions with volumes named as iSnapR_<xyz> will be given preference. If no such pre-paired session found, any existing pre-paired session will be picked.
2. If pre-paired sessions are not available, preference is given to target volumes with a special name set by the registry key ETERNUS_USE_VOLUME_LABEL. If there are no suitable volumes with the special name, the backup job will fail.
3. If no target volumes are available, the job will fail.