STATUS CODE 89: Increasing shared memory does not prevent backups from failing with error code 89 (problems encountered during setup of shared memory).

Overview:
It is possible that increasing the shared memory kernel parameters based on the calculations in the performance and tuning guides will not prevent backup from failing with a NetBackupStatus Code 89, especially when backing up a large number of Windows clients using the backup selection directive ALL_LOCAL_DRIVES.  

If the amount of shared memory configured in the kernel is adequate based on the shared memory formula, then other possible sources of the status 89 error will need to be investigated.

Troubleshooting:

Reducing the value configured in the /usr/openv/netbackup/db/config/NUMBER_DATA_BUFFERS file may resolve the problem.

Log files:  N/A

Resolution:

A shared memory calculation is used to determine the NetBackup media server recommended minimum kernel requirements. It is also used for every UNIX platform that has the option to set tunable kernel parameters (Solaris, Linux, HP-UX). In large environments that are growing, it does become obvious that the recommended minimum kernel parameters (the ones included in the installation guide along with shared memory requirements) are not sufficient and need to be increased.  At that point, NetBackup support would be unable to offer the specific values to which the parameters should be increased.

The following information from the Backup Planning and Performance Tuning Guide should also be taken into consideration when determining how much shared memory a media server should allocate:

"As a rule, the number of clients (separate physical hosts) per master server is not a critical factor for NetBackup. Ordinary backup processing performed by each client has little or no impact on the NetBackup server, unless, for instance, the clients all have database extensions or are trying to run ALL_LOCAL_DRIVES at the same time."

In summary, Status Code 89 can occur if there is not adequate shared memory allocated in the kernel.  That is not, however, the only possible cause of this error.  Assuming the kernel has enough shared memory configured, it is necessary to look at the other possible causes of the Status 89 error.