NetBackup Tape Drive SAN Multipath failover support with Oracle T10000D

[Priyeranjan]

Hi Team,

I would like to check for netBackup tape drive SAN multipath failover option. In current situation we have oracle T10000D tape drives and each drive has two SAN ports and Oracle says they support multipath means one port is not working another will serve data as load balance. Now when it comes to Netbackup, I really dont understand how the operation will be managed because as per my understanding if one active path fails then drive will be downed and it may freeze. At a time one path will be active that means configuraiton will be active/passive. Now my question is if one path fails will netbackup use other path, or we need to manually scan.

Oracle Document Info

Tape Drive Multi-Path

NetBackup does support multiple paths to a single tape drive. The paths can be discovered and configured automatically, but the configuration is active passive only. In the event of a path failure, the job running on the tape drive that has lost its path will be interrupted and the drive will be temporarily downed. NetBackup will then find the other path and bring the drive back online. If the job in progress had checkpoints enabled, the job will resume from the last checkpoint. If checkpoints were not enabled, the entire job will need to be rerun

One more thing i have found in Netbackup Device configuration guide

Multipath configurations (multiple paths to robots and drives) are supported only with the following configurations:

• Native path (/dev/nstx, /dev/sgx)
• The sysfs file system that is mounted on /sys

Does above statement confirms that multipathing will work? If yes then how?

If possible please repond to my querry ASAP. I will be very thankful.

Regards,

Priyeranjan

[mph999]

I am afraid the answer is not good:

https://www.veritas.com/support/en_US/article.TECH215781

[Priyeranjan]

Hi Martin,

Many thanks for your reply. I have seen same tech note before and looks like you are right because auto SAN path failover will not work. Now my question is Netbackup can scan multiple path of the drive i.e.if drive has two path then both path will be scanned and configured during device configuration wizard and storage unit will be created and when i will check the drive status in device monitor it will show two path of same drive. As Oracle has mentioned and also Veritas says active/passive configuration is supported, means one path fails another path will be used. Do you realize below action plan will throw some light on this issue.

-    Disable any third party/ OS multipathing software (In this case MPIO on Media Server).
-    Zone both port of tape drives with media server
-    Enable persistent binding 
-    Suspend/stop all backups
-    Run drive configuration wizard and configure storage unit with all path
-    Keep both path active on media server
-    Run  few test jobs and monitor tape drive behavior
-    Bring down active tape drive path manually during backup and check if netbackup is able to use another path         without any issue, i.e. no media stuck or scsci reservation 

Regards,

Priyeranjan

[mph999]

That looks like a reasonable test plan.