Re: Leaving dumps on the holding disk?
On 01/25/2015 10:27 PM, Jason L Tibbitts III wrote: My amanda server has a really large holding disk, because disk is cheap and because lots of disk striping generally equals better write performance. The usual restore operation I have to do is pulling things off of last night's backup, which involves waiting for the library to load things and such, and of course hoping that there's no problem with the tapes. But there's a good chance that the backup image I need was just on the holding disk, and if it hadn't been deleted then there would be no reason to touch the tapes at all. In fact, even with LTO6 tapes, I should still be able to fit several tapes worth of backups on the holding disk. Is there any way to force amanda to delay deleting dumps until it actually needs space on the holding disk? Or, is there any particular place I might start looking in order to hack this in somehow? Interesting idea! The main problem is that if you leave the dump in the holding disk, amanda will automatically re-flush (autoflush) them on the next run. There is no way to store the information about dump that are already flushed and dump that are not flushed. The amanda development branch have that capabilities. Implementing this feature will be a lot easier. Jean-Louis
Re: Leaving dumps on the holding disk?
I wonder if one could somehow use the AMVAULT command to do this? It serves to make a COPY of a dump tape (as I understand it). At the very least, you could have a cron job copy the tape back *off* of the tape, onto a spare corner of the holding disk that you had labeled as “virtual disk” tape storage. Or, no wait …..do that on-disk copy first. Have the holding disk data saved to another portion of the large disk area that is a “virtual disk tape storage” as your nightly backup tape. But since you really want a physical tape (I gather you do? I do.) then use AMVAULT to copy the virtual disk off to the real tape that you want. Every night. This would leave you with a copy of it on virtual disk.Which could be set up to have a very short recycle period, if you like? (Assuming you don’t have *that* much space to spare.) Maybe play with this idea a bit? Deb Baddorf Fermilab ( sorry for capitalizing words like AMVAULT — my mac keeps trying to change the spelling of words that I write) On Jan 26, 2015, at 12:09 PM, Jason L Tibbitts III ti...@math.uh.edu wrote: JM == Jean-Louis Martineau martin...@zmanda.com writes: JM The main problem is that if you leave the dump in the holding disk, JM amanda will automatically re-flush (autoflush) them on the next run. JM There is no way to store the information about dump that are already JM flushed and dump that are not flushed. Well, I figured as a hack, they'd just get renamed in some way that the code would ignore when it comes to flushing things, and a cron job would nuke the oldest ones every few minutes if the disk is full. But of course that wouldn't integrate the held dumps with the regular restore process. JM The amanda development branch have that capabilities. Implementing JM this feature will be a lot easier. Cool. It's not as if I'm in a huge hurry. I just thought it might be nice to use the holding disk for more than just a very temporary staging area. - J
Re: Leaving dumps on the holding disk?
JM == Jean-Louis Martineau martin...@zmanda.com writes: JM The main problem is that if you leave the dump in the holding disk, JM amanda will automatically re-flush (autoflush) them on the next run. JM There is no way to store the information about dump that are already JM flushed and dump that are not flushed. Well, I figured as a hack, they'd just get renamed in some way that the code would ignore when it comes to flushing things, and a cron job would nuke the oldest ones every few minutes if the disk is full. But of course that wouldn't integrate the held dumps with the regular restore process. JM The amanda development branch have that capabilities. Implementing JM this feature will be a lot easier. Cool. It's not as if I'm in a huge hurry. I just thought it might be nice to use the holding disk for more than just a very temporary staging area. - J
Re: Leaving dumps on the holding disk?
Mon, 26 Jan 2015 kirjutas Jason L Tibbitts III ti...@math.uh.edu: The usual restore operation I have to do is pulling things off of last night's backup, which involves waiting for the library to load things and such, and of course hoping that there's no problem with the tapes. But there's a good chance that the backup image I need was just on the holding disk, and if it hadn't been deleted then there would be no reason to touch the tapes at all. In fact, even with LTO6 tapes, I should still be able to fit several tapes worth of backups on the holding disk. Is there any way to force amanda to delay deleting dumps until it actually needs space on the holding disk? Or, is there any particular place I might start looking in order to hack this in somehow? I don't know, but there is an alternative approach you could use. If your tapes are big enough to hold several days worth of dumps, you could delay writing dumps to tape until enough of them have gathered on the holding disk to fill a tape. That is what I am doing here. Relevant parameters in my amanda.conf: flush-threshold-dumped 100 flush-threshold-scheduled 100 taperflush 100 autoflush yes -- Toomas Aas Tartu linnakantselei arvutivõrgu peaspetsialist tel 736 1274 mob 513 6493
