Limitations of the MSDP volume group
The MSDP volume group does not support the following:
Supports an isolated recovery environment (IRE) with the following configuration:
The clock time and time zone on the MSDP servers must be consistent with the MVG server, and both should run on Linux platforms.
One MSDP server should not be used by multiple MVG servers.
Does not support universal share. You can use the individual MSDP servers for universal share as it is.
Supports Image sharing on regular MSDP servers. For the backup images, which were created through MVG volume, you can use regular MSDP server as it is for image sharing.
No deduplication across nodes.
Limited data balancing across nodes.
To reduce the impact on deduplication rate, we restrict the reassignment of one client policy on a limited number of nodes. Manually changing the assignment of one client policy is supported. You can use an MSDP command to change that on a limited number of nodes.
A single large backup cannot spread across nodes.
If it is an MVG volume of local volumes (PureDiskVolumes), it may be seen as an issue as there is space for the MVG volume, but not enough space for any single node to store the backup data.
When the issue happens, as an alternative, you can move the large backup policy to an MVG volume of cloud volumes, or use "MSDPLB+" policy and enable multistream backup.
The backup jobs of a multistream backup policy will go to the same node unless it is an "MSDPLB+" policy. Do not use MSDPLB+ policy unless necessary as there is no data deduplication across the MSDP nodes.
Note:
"MSDPLB+" policy means a backup policy of which the name starts with "MSDPLB+". Starting from NetBackup 11.0, it also means a backup policy with the policy attribute Enable Multiple MSDP nodes is enabled.