Hello, I was trying to think through what we want our dump cycle and total number of tapes to be, and I realized that I wasn't quite clear on some things.
We have a changer with a capacity of 33 tapes. We have Amanda configured for a 7 day dump cycle, backups every night. Our backups currently use only 1 tape per run. I'm trying to figure out what our "minimum service level guarantee" would be if we used 33 tapes in our changer and we assume that it's 1 tape per run. Are the following statements correct? 1. We will have a full dump of any given partition somewhere on the most recent 7 tapes and that to restore a file to any given date in the past 7 days would take at most 7 tapes/steps but on average 3.5 tapes/steps. 2. We can retrieve a file as it existed on any date in the past 27 days, and possibly as it existed on days 28-33 (with Amanda shifting around full dumps, you never know how old the oldest full dump available will be, but you will know that it will be at least 27 days old, right? My thinking is that to retore any file you need to start with a full dump, and with 33 tapes and a 7 day cycle, if day 34 was a full dump, days 33, 32, 31, 30, 29, and 28 could have been incrementals before a forced full on 27. Hence, it seems you are guaranteed to be able to retrieve any file as it existed 27 or less days ago. I don't really want to start using Amanda in the manner of CVS where I start retrieving older versions of files where newer ones exist on a regular basis, but I would like to know the boundaries for when we do need to do this. Thanks, Fran -- Fran Fabrizio Senior Systems Analyst Department of Computer and Information Sciences University of Alabama - Birmingham [EMAIL PROTECTED] (205) 934-0653
