I am backing up my Netbackup catalog backups to NAS share with 1 month retention. Since my enviroment is grown, my catalog backup is also grown and can not keep all 1 month backups in the NAS share. I cant expand the NAS share either. So what i did was, i have set up DSSU which duplicates the images from NAS share to OST storage. my high and lower water mark level is 80 % and 30 % respectively. Looks like when DSSU duplicates the images from NAS share, it takes random images and duplicates. I was thinking that it will start from oldest images to duplicate(like SLP). i want to know How DSSU picks the images from primary storage? if i want DSSU to pick oldest images for the duplication, what needs to be done. your help will be appreciated.
For DSSU behaviour see : Description of NetBackup Disk Staging Relocation Behavior
Also consider as a quick fix to compress the Netbackup catalog - it should give at lest 30-50% space savings
Thank Nicolai for the information. I already did go through your first link. It has the information about grouping the images but it does not tell me how it picks the images for the grouping. My intention is to keep latest catalog backups in NAS share(at least 2 week2) and remaining can be moved to OST storage. Thats why i want DSSU to group old images and keep latest catalog images in NAS share...you know catalog recovery from OST dedup storage is complicated than from NAS share/tapes. Since SLP does not support basic disk storage unit, i could not use SLP for the duplication. So only option is DSSU. is there any other option to meet my expectations?
I am not very much interested in doing compression for catalog backup. We have enough storage to keep catalog backups. Total catalog backup size is about 200 GB as of now.
What OST device do you have ?. Can you backup the catalog direct to a NFS share on the OST device ?- This is the way I did it on data domain/StoreOnce. Catalog recovery from a basic disk cannot be simpler.
You as a end user cannot control DSSU behaviour except the staging size behaviour. If replication speed is good it should not cause any problems as Netbackup will try to keep images on disk as long as possible and only if high watermark is reached delete the oldest images.