Netbackup Status code 2074 & disk volume is down

Symptom:
Backups to a Disk Storage Unit (DSU) intermittent fails with status code 2074 and an “EMM status: Disk volume is down” message.

31-07-2011 15:24:08 – requesting resource jpto-dsu
31-07-2011 15:24:08 – requesting resource affmaster01.NBU_CLIENT.MAXJOBS.somehost001.acme.net
31-07-2011 15:24:08 – requesting resource affmaster01.NBU_POLICY.MAXJOBS.WIN_FS_JPTO
31-07-2011 15:24:08 – awaiting resource jpto-dsu.
31-07-2011 19:32:27 – Error nbjm (pid=30793) NBU status: 2074, EMM status: Disk volume is down

Cause:
MacAfee was scanning the backup images written to the DSU.

Resolution:
Exclude MacAfee from scanning the Netbackup Images files in the DSU area.

See also Symantec Tech Note:
General recommendations for virus scanner exclusions working with NetBackup

Next tech note has a full description of how to exclude Netbackup in Mcafee

3RD PARTY: NetBackup Services are randomly shutting down on Windows servers after applying a patch for McAfee McShield 8.5 or 8.7i