Overview: NetBackup Vault is not balancing duplication jobs equally across multiple write drives.

Troubleshooting:

NetBackup VAULT records vault activity in a Session ID or SID.
In this example we'll use VAULT SID2571.

The log needed is the detail.log.
/install_path/netbackup/vault/sessions/MyVault/sid2571/detail.log

VAULT will first match and sort previous backups by retention level and place the backups into batch jobs for duplication. If the vault profile contains multiple write devices each batch is assigned a different write device.

In SID2571 two duplication batches exist (#Batches=2); one batch for each Retention Level (RL).

SID2571 - detail.log:

08:33:17.990 [18694] <2> vltrun@LogDuplicationBatches^2571: Logging matched-up batches
08:33:17.990 [18694] <4> vltrun@LogDuplicationBatches^2571: DupRule for MS= #Batches=2
08:33:17.990 [18694] <4> vltrun@LogDuplicationBatches^2571: DiskBatchInfo:
08:33:17.990 [18694] <4> vltrun@LogDuplicationBatches^2571:   MS=bvlbs05 #IMGs=149 RL=5 DT=1 CN=-1 SZ=435875045
08:33:17.990 [18694] <4> vltrun@LogDuplicationBatches^2571: DiskBatchInfo:
08:33:17.990 [18694] <4> vltrun@LogDuplicationBatches^2571:   MS=bvlbs05 #IMGs=1 RL=10 DT=1 CN=-1 SZ=32

In this example, the duplication jobs are not equally split per image or size (SZ).
Note: NetBackup VAULT does not sort and create batches per size.

The first batch includes 149 images of Retention Level 5: (#IMG's=149 RL=5)
The second batch includes 1 image of Retention Level 10: (#IMG's=1 RL=10)

Note: By default NetBackup will not allow multiple retentions per media and in this example each batch contains only images of the same retention.

To determine if this is operating as designed:

1. From a command line execute bpretlevel to determine the retention levels.

# /usr/openv/netbackup/bin/admincmd/bpretlevel

This is only a small portion of the entire output.

Retention  Retention  Equivalent

 Level     Period       Days

5     3 months       93

10     1 day          1

As displayed, RL 5 = 3 months and RL 10 = 1day.

2. From a command line execute bpgetconfig to determine if the option to allow multiple retentions is set. Note: This will show the master server setting.

# /usr/openv/netbackup/bin/admincmd/bpgetconfig -g master_server -L
ALLOW_MULTIPLE_RETENTIONS_PER_MEDIA = NO

3. From a command line execute nbemmcmd -listsettings -machinename media_server to determine each media server setting.

# /usr/openv/netbackup/bin/admincmd/nbemmcmd -listsettings -machinename media_server_1
ALLOW_MULTIPLE_RETENTIONS_PER_MEDIA="no"

# /usr/openv/netbackup/bin/admincmd/nbemmcmd -listsettings -machinename media_server_2
ALLOW_MULTIPLE_RETENTIONS_PER_MEDIA="no"

Resolution - No action required:
In this example the master and media servers are set with default values and VAULT is working as designed by creating duplication batches based upon retention level.