bob944 wrote: >>> Dudes is there any way of saying how much space is left >>> on a particular tape? I have had a look around but am a >>> bit lost. >>> >> Yeah, run bpmedialist and compare with vmquery. >> > > That answer makes no sense. > > Dave, a tape holds as much as it holds, period. > > In contrast to a disk (has _exactly_ so many cylinders/tracks/sectors > and is usually not compressed); tapes write varying lengths of data, > separated by gaps of different sizes; usually compressing data with > variability in the data, in its fit in the drive buffer, in the firmware > algorithm on that drive; with unpredictable skips over flawed patches of > tape; and to tape length which is not uniform. The same tape, written > in the same drive with the same source data can vary; the same tape, > same drive, backing up something different will likely be quite > different. Throw in the variables and and... well, I've seen a range of > 4xxGB to 12xxGB on full SDLT600 tapes, for instance. > > An available_media listing with a bunch of full tapes will show you the > variability and give you a rough guide of what to expect from a given > pool and retention (more variability if you use one pool for many/all > types of backups, less if you have pools which handle specific clients > and specific, non-volatile data). > > When a tape hits EOM (Simon: End Of Medium to your question; used to be > End Of Tape by detecting a foil sticker) and NetBackup moves on to > another tape, you have zero space left. Anything else is an > approximation. > > > THanks for that. Was king of thinking that myself from looking at bpmedialist and seeing some tapes which were full had less than others. I guess it depends how much the data on disk took up but can be compressed onto the tape. Some files are perhaps already compressed and so that particular job used a certain tape and the compression could not be made any more.
Thanks I was just trying to work out which tapes to take out as i have 4 in one volume pool and i only need 1 really ( as its for logs ) so didn't want to take one out with loads of space left on it. I was just wondering if there was something which said although certain amount of the tape is used as its a DLT 35/70 it has X kb left. Cheers _______________________________________________ Veritas-bu maillist - Veritas-bu@mailman.eng.auburn.edu http://mailman.eng.auburn.edu/mailman/listinfo/veritas-bu