At Sat, 02 Oct 2010 10:15:29 -0400 [email protected] wrote: > > On Sat, Oct 02, 2010 at 09:05:44AM -0400, Robert Heller wrote: > > Why does Amanda do multiple level 0 backups? I only want 1 (and only > > 1) level 0 backup (of any given disk) in the backup cycle (4 weeks / 28 > > days). The documentation for the bump* parameters is not clear (to > > me). I want Amanda to aggressively bump dump levels. > > Hmm, I thought the descriptions in the amanda.conf(5) manpage > were pretty clear.
They are only *sort of* clear. There really isn't a clear (with examples!) explaination exactly when amanda bumps levels. > > [snip] > > bumpsize 10 Mb # minimum savings (threshold) to bump level 1 -> 2 > > bumppercent 0 # minimum savings (threshold) to bump level 1 -> 2 > > bumpdays 2 # minimum days at each level > > bumpmult 1 # threshold = bumpsize * bumpmult^(level-1) > > Two changes would increase the likelyhood of bumping levels: > change bumpsize to a smaller value (eg. 1 Mb or 500 Kb) > change bumpdays to 1 > > > I don't have enough virtual tapes to do more than one level 0 backup in > > a backup cycle. > > Yeah, I see that your setup is: > > > dumpcycle 4 weeks # the number of days in the normal dump cycle > > runspercycle 28 # the number of amdump runs in dumpcycle days > > tapecycle 30 tapes # the number of tapes in rotation > > And you are telling amanda it can use up to 56 tapes per cycle. > > > runtapes 2 # number of tapes to be used in a single run of amdump > > I hope very few dumps take more than one tape, like none :) Most of the incrs should take well under 1 tape. I am only doing incrs on /home and the /var/... file systems. Fulls only on /,/nfsroot,/boot, and /usr (one full per month). /home is large (in contains DVD ISOs of CentOS), but does not really change much. > > When the Wendell Free Library adds 2 or 3 DVDs to its filesystem, > > > /dev/mapper/WendellFreeLibrary-dvdisos > > 34G 177M 32G 1% /dvdisos > > it will never backup because its size will be greater than > your tapesize * your runtapes setting. The dvdisos FS is only for ISOs that are about to be burned. Nothing is kept there long term. Long term stuff would land on /home. /dvdisos is a place to put ISOs of backup 'tapes' before burning them to DVD-Rs. Once burned, the ISO file is deleted and the 'tape' would be marked for recycling. > > Even if your amdumps only use 1 tape per run and you get > the aggressive bumping you seek, I think you are on the > edge of a disaster. Suppose a DLE gets its level 0 on > day 1 and incrementals for the rest of the cycle (days 2 > to 28). On day 29 it gets its regularly scheduled > level 0 and on days 30 and 31 it gets incrementals. But > that last incremental wipes out the first level 0 and > makes all 27 of its incrementals lose much of their value. > My plan is to burn the fulls and the level 1s to DVDs each month (that is why the 'tapes' are 4.3 gig in size. What I *was* doing was a simple Tcl script that did (stagered) full dumps during the first week of each month, and then a Tower Of Hanor series of incrementals (with level 1s on Sunday), and then burning the level 0s and level 1s to DVD-Rs each month. I am hoping Amanda would do things in a way to let me do much the same, but it is not looking that way (so far). I may revert back to what I was doing and give up on Amanda... What I *was* doing worked reasonably well. I thought I could use Amanda to create a 'database' of backup 'tapes' (really DVD-Rs), instead of the somewhat ad-hoc way I was doing things (mix and match to fit compressed dumps onto DVDs, using split as needed). So far, Amanda has not really bought me much. I also was going to use Amanda to make backups of the 'satelite' systems -- the one 'thick' workstation (the only one with its own disk -- all of the others are diskless) and the two mess-windows boxen, but that is actually somewhat less critical. (The Tower Of Hanoi dump level sequence was lifted from the man page for dump.) > Jon -- Robert Heller -- 978-544-6933 Deepwoods Software -- Download the Model Railroad System http://www.deepsoft.com/ -- Binaries for Linux and MS-Windows [email protected] -- http://www.deepsoft.com/ModelRailroadSystem/
