Chris Hoogendyk schrieb: > > > Stefan G. Weichinger wrote: >> Patrick M. Hausen schrieb: >> >>> Hi! >>> >>> On Wed, Aug 01, 2007 at 11:45:00AM +0200, Ralf Auer wrote: >>> >>> >>>> thanks, but does this also mean, that in future times I have >>>> always to >>>> put the tapes in ...-02-06-03-... order, or does *she* switch over to >>>> 02-06-03-04-05-01-02-03-04-05-06-01... automatically, so that the >>>> newest >>>> tape is in fact added at the end of the list after one full cycle? >>>> >>> Amanda may reorder tapes to be used any time, anyway. >>> Set up a cron job that executes amcheck every morning and >>> sends you the ouput via email. It contains the information >>> which tape Amanda expects next. >>> >> >> Ralf, Patrick is correct: >> >> Amanda tracks tape usage and tells you which tape to insert. >> Either by running amcheck or 'amadmin <conf> tape', and the report mail >> of amdump also contains that info. > > just to clarify this a bit... > > amanda doesn't re-order tapes. It takes them as they come (as you give > them to it), as long as they fit amanda's algorithm according to your > cycle. Rather than go over it all here, look at the wiki documentation: > <http://wiki.zmanda.com/index.php/Taper_scan_algorithm>. > > With a tape library, amanda is not going to scan the whole library. It > is going to look at the current slot. If the tape in that slot is > acceptable according to the algorithm, it will use it. Otherwise it will > go on to the next slot until it finds an acceptable tape or runs out of > slots. > > So, while amanda will tell you what tape it expects on the next run (the > least recently used one), it will take what you give it as long as it is > acceptable. It's not going to take that '06' and put it "back in order". > The order as far as amanda is concerned is according to the date the > tapes were written. The label is just a pattern you specify that amanda > will require a match on. The one time I lost a tape, it was > bio-daily-007. I labeled a new tape bio-daily-0072, put it in the > current slot, and let amanda use it. So my order now goes through 006, > 0072, 008, etc. That just reminds me that it is a tape I replaced. > > If you look at the tapelist file, you will see the dates that all the > tapes were last written to. If you do `amtape <conf> update`, amanda > will scan all the slots in your changer and you will see what you have > in every slot. > > And, as others have said, having dumpcycle=runspercycle=tapecycle is not > good. I have 5,5,35, which gives me 6 weeks+ of full backups. > > You are responsible for your tapes and your cycle, but amanda will > always do the right thing as best as it can and will keep you informed. > Running amcheck in the afternoon off cron will result in amanda sending > you an email if things aren't ready to go for the night backup. It will > tell you what it was expecting and exactly what was wrong. The report > amanda sends you after a backup tells you exactly what it did and what > tapes were used or if there were any errors with the tape. And, if you > come in in the morning and don't have an email report, and wonder what > the heck is going on, you can run amstatus and it will give you full > details of exactly what is going on, what has been completed, how far > along stuff is that is being done, and what is waiting to be done.
Nice summary, Chris. Why not contribute stuff like this to the docs/Wiki? Thanks, greetings, Stefan.
