The Cohesity Certified Protection Professional – NetBackup Appliances (COH-285)

With ALL_LOCAL_DRIVES and Allow multiple data streams enabled, NetBackup can split each client backup into separate streams per drive or file system; Cohesity documentation states that NetBackup backs up the client and “splits the data from each drive” into its own stream when multiple data streams are enabled. However, the number of streams that can run concurrently is still constrained by job limits. Cohesity’s policy documentation states that concurrent stream count is affected by Maximum jobs per client, Limit jobs per policy, and related storage limits; when Maximum data streams is not explicitly set, NetBackup uses the lower of Maximum jobs per client or Limit jobs per policy. The default Maximum jobs per client is one job, so only one backup stream per client can run. With five clients, that means 5 active backup jobs, not 15.

The storage unit’s Maximum concurrent jobs = 15 does not restrict restores, because Cohesity states this setting controls backup and duplication traffic, not restore jobs. The disk pool’s Maximum I/O Streams = 20 limits read and write streams; restores read backup images and backups write them. Five backups plus ten restores equals 15 total streams, so all 10 restores can run.

The method that is not able to provide historical performance information is running nbperfchk on the command line. nbperfchk is a standalone diagnostic utility used to test current disk I/O and network transfer rates. Official NetBackup guidance describes it as a tool used to determine base disk performance for backup disk devices and network throughput to a disk volume; it generates performance results from the test being run, not from prior NetBackup jobs or stored catalog/reporting data. By contrast, the other options are valid historical performance sources. The Activity Monitor job details provide job-level performance fields such as Start Time/End Time, Elapsed Time, KB per Second, and Kilobytes. The All Log Entries report can be run for a selected Date/Time Range and displays transfer-rate information useful for evaluating backup performance and predicting future backup windows. OpsCenter Disk and Tape Device Activity reports provide storage-device activity, utilization, throughput, and capacity-related reporting across NetBackup storage resources. Therefore, nbperfchk is a point-in-time benchmarking tool, not a historical reporting mechanism. References/topics: NetBackup performance evaluation, Activity Monitor job details, All Log Entries report, OpsCenter Disk and Tape Device Activity reports, and nbperfchk performance testing.

The correct action is to move E02003 to the scratch_pool. Cohesity NetBackup documentation states that the Policy volume pool specifies the default media pool for policy backups, and whenever a new volume is required, NetBackup allocates it from that indicated pool. It also identifies the scratch volume pool as the mechanism that lets NetBackup automatically transfer volumes when another pool has no media available. In the output, the policy requires server_tapes, but that pool has no usable available HCART2 media: E02007 and E02008 are active with retention levels 1 and 3, E02005 is full, E02006 is frozen, and E02004 is FULL/FROZEN. Unfreezing E02004 would not solve the issue because it remains full. NetBackup also stores tape backups with other backups at the same retention level by default, so this retention-level mismatch matters for active tapes. E02003 is the only unassigned, available HCART2 backup tape. Placing it in the scratch pool allows NetBackup to move it automatically into server_tapes when the job requests new media. References/topics: Policy volume pool, Scratch volume pools, retention-level media selection, and status 96 media allocation troubleshooting.

The correct resources are the operating system logs and the robtest command. The failure is not a client file-read problem; it occurs when bptm requests tape media and the robot cannot complete the operation. Cohesity NetBackup documentation describes the tape workflow: bptm reserves drives and issues mount requests through the Media Manager and robotic daemons, which perform the physical media mount. When the job detail reports “Robot operation failed” and “All drives down,” the fault domain is tape device access, robotic control, drive visibility, zoning, library state, or OS-level SCSI communication. Official troubleshooting guidance states that NetBackup uses OS-level commands and drivers for tape operations, and recommends starting at the OS and hardware layer and checking OS system/event logs. The robtest utility is also directly relevant because it issues basic SCSI commands to a robotic device attached to a NetBackup media server and can test drive status, slot status, move operations, and robot readiness. Options B, C, and D are less relevant: bpbkar is a backup client read process, nbdevconfig is primarily disk-storage configuration, and bpmedia manages media records rather than robotic motion or drive connectivity.

The unavailable feature is Spanning volumes. In NetBackup cloud storage, disk-volume spanning is not supported by cloud vendors for backup images. The official NetBackup Cloud Administrator’s Guide lists cloud-storage limitations and explicitly states that cloud vendors do not support disk volume spanning of backup images. This makes option C the only correct answer. The other options are valid cloud-storage configuration capabilities. Compression is available in the Cloud Storage Server Configuration Wizard; the wizard provides a setting to compress backup data before writing to cloud storage. Encryption is also a supported wizard function, including AES-256 encryption and KMS-related configuration for data written to cloud storage. Secure Sockets Layer is likewise a supported connection property: NetBackup cloud storage server properties include USE_SSL and USE_SSL_RW, with SSL enabled by default for control APIs and read/write operations. Therefore, because encryption, SSL, and compression are configurable cloud features, while disk-volume spanning is a documented cloud-storage limitation, the correct selection is C. Spanning volumes. Reference topics: NetBackup Cloud Administrator’s Guide, “Configuring cloud storage,” “Cloud storage server connection properties,” and “Support limitations for NetBackup cloud storage.”

( The NetBackup documentation landing page includes a variety of resources, including whitepapers, guides, and videos, on best practices for NetBackup, enabling users to optimize their use of the product.)

The correct location is Media and Device Management > Device Monitor > Disk Pools. In NetBackup, the Devices > Disk Pools view is primarily used to view configured disk pools, manage disk-pool properties, delete disk pools, or perform inventory-related actions. It is not the operational monitoring location used to change the runtime state of a disk pool. Cohesity documentation distinguishes the disk-pool management view from state monitoring; for example, it states that disk pool state is UP or DOWN and that the state is displayed in the Status column when locating the disk pool. The classic NetBackup Administration Console procedure states that to change disk pool state, the administrator selects Media and Device Management > Device Monitor, opens the Disk Pools tab, selects the disk pool, and then chooses Actions > Up or Actions > Down. Cohesity’s disk-pool state guidance also notes that changing a disk pool to DOWN requires the disk pool not to be busy; assigned backup jobs must complete or be canceled before the state change succeeds. Therefore, the correct console path is option B.

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)

The correct feature is Synthetic backups. Cohesity NetBackup documentation explains that, in a traditional full backup, all files are copied from the client to the primary or media server, even if the files have not changed. With a synthetic full backup, NetBackup combines the previous full backup with subsequent incremental backups on the media server to create a new full image. Because the processing occurs on the primary and media servers rather than repeatedly reading all data from the client, synthetic backups reduce client-to-server network traffic; files are transferred over the network only once. Synthetic backups can also be written to disk storage units, making them appropriate for an AdvancedDisk target backed by a high-speed disk array. This fits the scenario because Windows and Linux file servers map to MS-Windows and Standard policy types, which are supported for synthetic backups. NetBackup Accelerator is not the best answer here because Accelerator requires supported disk targets such as MSDP, NetBackup appliance storage, cloud storage, or qualified OST storage, not a generic AdvancedDisk storage unit. Client-side deduplication similarly requires deduplication storage, and network resiliency improves fault tolerance rather than reducing backup traffic. References/topics: Synthetic backups, AdvancedDisk storage units, backup traffic optimization, and Accelerator requirements.