Cohesity Updated COH-285 Exam Questions and Answers by nia

The correct logs are the NetBackup bpfis logs on the client and the operating system logs on the client. The job details show a Windows snapshot failure: GLOBALROOT\Device\HarddiskVolumeShadowCopy..., status: 156: snapshot error encountered, and status: 1542: An existing snapshot is no longer valid. In Cohesity NetBackup snapshot processing, bpbrm starts bpfis on the client, and bpfis creates the snapshot of the client data and returns snapshot completion status. Therefore, the bpfis client log is the primary NetBackup log for the snapshot creation, mount, and delete phases.

Because this is a Microsoft Windows client snapshot issue, the Windows operating system logs are equally important. Cohesity’s status 156 troubleshooting topic identifies VSS framework failures and notes that VSS-related application events may be written on the affected Windows system; it also references bpfis log content for snapshot failures. The media server bpbrm log can show orchestration status, but it usually reports what the client-side snapshot component returned. The bptm log is for media/data movement and is not the best source for VSS snapshot root cause.

The replication job starts when the force interval for small replication jobs is reached. NetBackup SLP settings control how Storage Lifecycle Policy jobs are maintained and executed for the selected primary server. Cohesity documentation identifies these as SLP settings used to customize how SLP jobs run. For AIR replication batching, the controlling parameter here is SLP.MIN_SIZE_PER_REPLICATION_JOB. Official NetBackup documentation defines it as the smallest batch size that can run as a single replication job and states that the job does not run until enough images accumulate to reach that size, or until the force interval for small replication jobs is reached. (veritas.com)

In this scenario, three backups of 5GB each create only 15GB of eligible replication data. That is below the configured 20GB threshold, so NetBackup does not start the replication job based on size. Because the backup window has closed and no additional backup images will arrive, the batch cannot reach 20GB. NetBackup therefore submits the small replication batch when the oldest image reaches the configured 60-minute force interval. The force interval is specifically designed to prevent NetBackup from waiting too long before submitting a small replication job. (veritas.com)