Apologies for the delayed reply, I've just got back from holiday...
For our backups, we use a full + incrementals and rotate the tape
sets nominally every 3 months. 4 tape sets are used, so we can go
back at least a year.
Yes, the full backups are not scheduled, but manually started. The
incrementals are automatic. The retention time is 'infinity'. This
means that we do not *have* to change tape sets at exactly 3 month
intervals. The tapes do not automatically expire, we have complete
manual control. It's a little unsophisticated and wouldn't suit a lot
of people, but it's versatile and for us it works well.
REMEMBER - the safety of your data is your responsibility
If it's important to you - ** MAKE A COPY ** or 2 or 3 or 4 or ........
There is only one certainty about storage systems - they *will* fail !
Wellcome Department of Imaging Neuroscience
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