Hi all, I have a query regarding tape usage:
Analysis: We currently have TSM 5.2 installed on a WIN2k Server platform backing up appx. 50 nodes to 2 disk pools and then migrating to LTO tapes in a 3583 library, one copy for offsite vault and one copy to remain onsite within the tape library. We have 60 available slots for LTO volumes as we leave the I/O drawer free to take volumes in and out of the library. We are using 100gb native LTO volumes. We have 3 nodes that are configured to backup using collocation. Problem: We are constantly running at full capacity within the library (always 59 Private volumes) leaving only one slot for scratch. Because we have 3 collocated nodes and produce a dbbackup everyday to go offsite we need a minimum of 5 free slots (assuming all other backed up data for other nodes does not exceed 100Gb). When I issue 'q eve * * begind=-1' to check the previous evenings backups I am usually shown that most nodes have completed but often have only 2 tapes to go offsite (inc. the dbbackup) suggesting that collocation is not happening. Aside from this, when I issue a script to check what space I am able to relaim from the onsite tapes (in order to free up some slots for scratch volumes) I am presented with the following (I have omitted the offsite copy LTOs): STGPOOL_NAME VOLUME_NAME PCT_RECLAIM ACCESS ------------------ ------------------ ----------- ------------------ BACKUP_TAPE 000411L1 43.8 READWRITE BACKUP_TAPE 000466L1 43.5 READWRITE BACKUP_TAPE 000362L1 43.0 READWRITE BACKUP_TAPE 000382L1 42.6 READWRITE BACKUP_TAPE 000380L1 39.6 READWRITE BACKUP_TAPE 000529L1 39.1 READWRITE BACKUP_TAPE 000632L1 38.7 READWRITE BACKUP_TAPE 000563L1 38.4 READWRITE BACKUP_TAPE 000418L1 35.4 READWRITE BACKUP_TAPE 000403L1 34.6 READWRITE BACKUP_TAPE 000572L1 33.7 READWRITE BACKUP_TAPE 000364L1 31.4 READWRITE BACKUP_TAPE 000564L1 28.8 READWRITE BACKUP_TAPE 000402L1 28.5 READWRITE BACKUP_TAPE 000495L1 25.8 READWRITE BACKUP_TAPE 000391L1 25.6 READWRITE BACKUP_TAPE 000412L1 22.9 READWRITE BACKUP_TAPE 000453L1 22.8 READWRITE BACKUP_TAPE 000501L1 21.3 READWRITE BACKUP_TAPE 000413L1 16.6 READWRITE BACKUP_TAPE 000612L1 16.1 READWRITE BACKUP_TAPE 000470L1 14.8 READWRITE BACKUP_TAPE 000618L1 11.4 READWRITE BACKUP_TAPE 000395L1 11.1 READWRITE BACKUP_TAPE 000607L1 6.3 READWRITE BACKUP_TAPE 000388L1 3.2 READWRITE BACKUP_TAPE 000422L1 2.4 READWRITE BACKUP_TAPE 000570L1 2.2 READWRITE BACKUP_TAPE 000516L1 0.0 READWRITE BACKUP_TAPE_COL 000463L1 44.7 READWRITE BACKUP_TAPE_COL 000600L1 42.9 READWRITE BACKUP_TAPE_COL 000575L1 41.4 READWRITE BACKUP_TAPE_COL 000530L1 40.3 READWRITE BACKUP_TAPE_COL 000540L1 37.7 READWRITE BACKUP_TAPE_COL 000605L1 35.7 READWRITE BACKUP_TAPE_COL 000417L1 34.7 READWRITE BACKUP_TAPE_COL 000457L1 33.0 READWRITE BACKUP_TAPE_COL 000437L1 32.4 READWRITE BACKUP_TAPE_COL 000644L1 29.5 READWRITE BACKUP_TAPE_COL 000415L1 28.4 READWRITE BACKUP_TAPE_COL 000581L1 28.3 READWRITE BACKUP_TAPE_COL 000583L1 28.3 READWRITE BACKUP_TAPE_COL 000601L1 27.7 READWRITE BACKUP_TAPE_COL 000452L1 26.3 READWRITE BACKUP_TAPE_COL 000414L1 24.9 READWRITE BACKUP_TAPE_COL 000464L1 23.1 READWRITE BACKUP_TAPE_COL 000477L1 22.4 READWRITE BACKUP_TAPE_COL 000416L1 22.2 READWRITE BACKUP_TAPE_COL 000502L1 20.6 READWRITE BACKUP_TAPE_COL 000545L1 19.2 READWRITE BACKUP_TAPE_COL 000360L1 15.0 READWRITE BACKUP_TAPE_COL 000379L1 7.7 READWRITE BACKUP_TAPE_COL 000515L1 4.6 READWRITE BACKUP_TAPE_COL 000596L1 4.5 READWRITE BACKUP_TAPE_COL 000559L1 1.9 READWRITE BACKUP_TAPE_COL 000442L1 0.6 READWRITE By looking at the 'PCT_Reclaim' I can see that 000516L1 has 0% of reclaimable space going up to 43.8% for the least used volume (000411L1). What I have tried to do to get some more usage out of my LTO volumes is issue a 'MOVE DATA <VOL_NAME> STGP=<DISK_POOL>' to move all the data from the least used volumes (making it READONLY before starting the process so TSM does not reuse the volume when it is returned to 'Scratch' status when empty) back to the disk pool to be migrated onto other onsite volumes. In effect I am running manual reclamations but as you can see from the output above it does not look like tape space is being managed as efficiently as it could be. I'm not sure whether this is to do with the way TSM has been configured or whether it is natural to see volumes used to differing percentages because of expirations, etc. Does anyone know how to get onsite LTO volumes to use closer to 100% of their capacity or are we expecting too much of our setup - do we need to start using 200Gb tapes (this will presumably mean we will need to replace our 4 existing drives)? Also, there are 27 onsite volumes for collocated nodes but only 3 collocated nodes - is there something I can check to ensure this is correct? Also, I am planning to delete some unused filespaces that will remove appx. 1.5Tb of data from our backed up data. Will deleting these filespaces invoke TSM to automatically purge the associated data that resides within the onsite/offsite volumes and will this mean that we will free up some slots within the library for scratch media? Hope someone can offer some suggestions. Regards, C. Adams. C. Adams IT Support Analyst WRC Holdings Limited This email and any files transmitted with it are confidential and intended solely for the individual(s) or entity(s) to whom it is addressed. Any views or opinions presented or expressed herein, are those of the author(s), and may not necessarily represent those of WWAV Rapp Collins Group or it's affiliates and representatives. 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