[quote="Jean-Louis Martineau"] set: flush-threshold-dumped 100 flush-threshold-scheduled 100 taperflush 100
> > > OK...I see that as documented here: > > http://wiki.zmanda.com/index.php/FAQ:Why_does_Amanda_not_append_to_a_tape%3F > > This would seem to allow full tape utilization without having to resort to > vtapes...I'm pretty sure I was already doing this and it didn't work > reliably...will try again. > > As I understand it, it would seem that the holding disk needs to be > *slightly* larger than the largest "tape" you are going to write to. I would > also seem that setting your backup files size to something pretty granular > (e.g. 1GB, 5GB or at most 10GB) would also help ensure you make full use of a > "tape". > > Now I've got a MASSIVE amount of IO capacity (300MB/s for the holding disk) > and since each "tape" is connected via its own dedicated SAS/SATA port I've > got about 100MB/s for as many tapes as I load at the same time (e.g. if I > load 5 I could be writing as much as 500MB/s)...of course this means I have > to split all of the source disks I'm backup up from across multiple Amanda > configs, right? > > But then that complicates things, I presume I need a dedicated holding disk > for each config? or can multiple configs share the same holding disk? > > If the former, then I presume what I really want is holding disks like this: > > drive 1 - 2TB - holding1 (DailySet1) > drive 2 - 2TB - holding2 (DailySet2) > drive 3 - 2TB - holding3 (DailySet3) > drive 4 - 2TB - holding4 (DailySet4) > > But now I'm confused...if I have all my flush params set to 100% and my > holding disk EQUALS the size of a backup "tape", how am I ever going to reach > the 100% threshold (would seem I would always be short by a few GBs)??? > > Perhaps I should go back to a stripped holding disk and carve out multiple > holding disks inside that and essentially oversubscribe the strip a bit, for > example: > > Stripe (drive1, drive2, drive3) - 6TB total > /hold/hold1 - config in amanda as 2.1TB > /hold/hold2 - 2.1TB > /hold/hold3 - 2.1TB > /hold/hold4 - 2.1TB > > ...or something like that...not sure if I can get away with oversubscribing > the Stripe that much...if not I think 4 2TB drives would work fine. > > This would allow any holding disk to easily grow to 2.0TB and thus fill a 2TB > (or 1.5TB) "tape" fully...yes/no? > > > Jean-Louis [url] +---------------------------------------------------------------------- |This was sent by baldw...@mynetwatchman.com via Backup Central. |Forward SPAM to ab...@backupcentral.com. +----------------------------------------------------------------------
