Fixed-in-stone parameters: 1) We outsource backup to central IT. 2) We are charged by the gigabyte, per backup run 3) The backup provider uses Legato 4) We would like to minimize backup cost. 5) Our data tends to be large and "clumpy" - in some random 1-to-4-day period, someone will write 10 gigs of data which will then sit there for months unchanged. 6) The data is on a very very reliable SAN so full restores are unlikely . We are willing to risk slow restores 7) We do individual file restores occasionally. No more than once a month max.
The current backup strategy, which we didn't design and *** initially were unable to negotiate changes in *** is to do a full every 59 days, then a weekly rotation of 7,6,4,5,3,2,1 (which is the same as doing 2,2,2,2,2,2,1 , I know). This strategy minimizes tapes needed to do a full restore, but for data like ours it tends to maximize *cost*. It's time to negotiate a change. The obvious thing would be to go to full every 59 days and a 1,2,3,4,5,6,7 rotation, but I'm thinking we should get a little creative. If we do a full on Sunday and someone dumps 10G on Monday, that 10G will get backed up eight times. I'm thinking the first week should start with a 1, second with a 2, third with a 3, etc ... (Legato has 9 levels, I believe...?) any thoughts, suggestions, clue bonks? -- Unix Systems Administrator Harvard Graduate School of Design _______________________________________________ Tech mailing list [email protected] http://lopsa.org/cgi-bin/mailman/listinfo/tech This list provided by the League of Professional System Administrators http://lopsa.org/
