We're really struggling with getting our backups onto tape. We have a Quantum Superloader 3 with a single LTO6 drive within - the unit is new.
We use the default forever forward incremental on our backup to disk storage where we retain 14 backup points - this works fine. We're also using the new Per VM backup repository option that came in V9 (I should say we're using V9/Hyper-V).
All we wish to achieve is weekly backup of our VM's to tape which is around 7TB of data. We have tried using Backup to Tape but having poured hours over this researching and trying, we cannot get this to occur without 2 x VBK being written for each VM which consumes enormous amounts of data on tape.
We therefore run a File to Tape back whereby we simply add our disk repository and hit go (we disable hardware compression, VSS and encryption). This works on the whole, but our problem is the length of time it takes. I.e. if we kick off first thing at 8AM, we need it to complete before 10PM the same day for when our nightly backup to disk job starts again, otherwise it will mess the tape job up with changing backup files in source repository.
We're seeing file to tape speeds of anything between 60MB - 150MB. When the job runs 130MB and over, we're within time frame but when it dips under 130MB (such as yesterday and Monday when it ran at an everage of 60-100MB!), we simply run out of time and have to cancel the job.
What are we doing wrong? Surely it can't be this difficult?
We were very excited about V9 with all of it's advancements, not least being able to simple do a backup to tape job without 2 x VBK's needing to be written, but at least our experience is that we have just the same issue.
We're at a point where we're considering scrapping tape and moving to rotated disk storage that we can take offsite weekly, both with 10Gbps cards within. At least this way we can do incremental backup copy jobs with a consistent speed (i.e. minus the 50MB - 150MB fluctuations we see with tape).
Waving the flag a little bit here guys, your assistance pls.