I found it on veritas support.
1. Expire the backup images by using the NetBackup GUI or the command line.
GUI initiated expiration:
Under Catalog, search for all existing images stored on the Media Server Deduplication pool. Make sure you search across the correct data range. Once found, right click and expire all images. You can check the Activity Monitor to verify if the Image Cleanup jobs succeeded successfully. This removal process dereferences the images from the NetBackup catalog.
Command line driven expiration:
a) Use the bpimagelist command to determine the backup IDs of the backups to be expired.
b) Run the command bpexpdate -backupid <backip ID> -d 0 -force -notimmediate to expire each image. The -notimmediate option prevents bpexpdate from calling the nbdelete command, which deletes the image. Without this option, bpexpdate calls nbdelete to delete images. Each call to nbdelete creates a job in the Activity Monitor, allocates resources, and launches processes on the media server.
c) After you expire the last image, delete all of the images by using the nbdelete command with the -allvolumes option. Only one job is created in the Activity Monitor, fewer resources are allocated, and fewer processes are started on the media servers. The entire process of expiring images and deleting images takes less time.
2. If the backup images are in a PureDisk Storage Pool (use case 2 only), run the PureDisk data removal policy in the PureDisk web based interface. Additionally for PureDisk (5020 or 5030 appliances) do not put 0 0 at the end of the command in step 6.
Note all commands for PureDisk Pool (5020 or 5030 appliances) are run from:
/opt/pdcr/bin
Note all commands are run from the following directories for msdp.
Unix: /usr/openv/pdde/pdcr/bin
Windows: <install_path>\veritas\pdde
3. Process the transaction queue twice. See Process the transaction queue.
crcontrol --processqueue
4. Monitor queue processing (busy:no means its complete)
crcontrol --processqueueinfo
5. Keep running queue processing until the queue reaches 0.
crcontrol --queueinfo
6. Once the queue is 0 and the queue processing says busy:no then start compaction
crcontrol --compactstart 0 0
7. Check that compaction is still running (busy:no means its complete)
crcontrol --compactstate
8. Check for Free space
crcontrol --dsstat
Can I proceed in the above way?