Gene,

Best regards,
ddaas

Gene Heskett wrote:

On Saturday 26 February 2005 15:19, ddaasd wrote:

So, I will have 16 tapes. How can I optimize their usage?
You say I should keep 1 or 2 tapes to replace a defect one. So I
have 15 working tapes.

I would like not to backup in weekend because there is no activity.

My Dell PowerVault has an auto-changer with 8 slots for 8 tapes.
I would like to have 8 tapes offsite and to change them once a week.

Unless you are going to use a runtapes greater than 1, you will not use 8 tapes a week when the runspercycle is only 5. Thats up to you. However, if in a given week, you only actually used 6 tapes, then amanda will get upset if you take all 8 tapes offsite.

I don't recall what the capacity of a powervault tape is so you'll have to judge that for yourself. I think what you will wind up doing though, is to remove for offsite storage, only those tapes that have actually been used according to the emails it will send you, or from the printouts if you have that enabled, something I'd also recommend. Whether its 8 tapes if it runs to the second tape some nights AND you have runtapes = 2, or 5 (the minimum it would use in 5 runs that week), those are the ones that should go to offsite storage.

I detect a bit of do it my way urge in these messages, rather than amanda's way, and while you may be able to force the issue by constraining amanda, amanda will work much better in the long run if you just let amanda do what amanda does best. You will get more efficiency in terms of tape use by just letting amanda 'do her thing'. It rather reminds me of an old saw about dogs and cats:

To a dog, you are the master.  To a cat, you are just staff.

Amanda is a cat.

What would be your values for the most important parameters from
amanda.conf (dumpcycle, runspercycle, runtapes etc).

I'd suggest:
dumpcycle 7, runspercycle 5, tapecycle 15.

This will, assuming 'runtapes' defaults to 1, give you backups 3 generations deep. And one spare tape. Also less paranoia about losing it all. :-)

This will work unless you have enough data to require a second (or more) tape per run.

Thanks a lot,

ddaas

Gene Heskett wrote:

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