On Wed, Jan 03, 2018 at 06:22:41PM -0500, Winston Sorfleet wrote: > On 2018-01-03 05:46 PM, Chris Miller wrote: > > Hi Jean-Louis, > > > > A vtape do not reserve the space, it only use the space of the > > dump you put on it. > > The vtape size should be the maximum size of any days or larger, > > they could be 120GB or 2TG, the result will be the same. > > Some vtape will use 5GB, some will use 120GB. > > > > Thanks very much. That is quite helpful. > > > > Is it possible to re-use a vtape for several successive backups? If > > the vtape were twice the size of a level 0 backup, then the level 1 > > backups would be appended, but the next level 0 would be too large and > > would trigger a new tape. > > > > Additionally, How do I configure larger cycles, meaning, I will use > > 150GB each week, and 2TB can hold 13 weeks. How do I tell Amanda that > > after 13 weeks, she should start over by deleting the oldest vtape? > > That's exactly what it will do, unless you explicitly tell Amanda that a > tape is out of commission. So, just like your traditional robot, it > will cycle. >
One parameter you specify is how many tapes (minimum) you have in rotation. Amanda will not reuse any tape until it has used that many tapes. I presently have 240 vtapes of 100GB each spread over 6 hard disks. I have specified my "tapecycle" as 140, not 240. All 240 tapes are used in sequence and then things rotate back to the beginning. But the lower number is my protection against one of the disks failing and amanda not having anywhere to put new backups. > HOWEVER, note that Amanda will not write to a tape that has been > recently written, whether it's 5 GB or 150 GB. It does /not/ append to > tapes (barring some painful and unnecessary manual configuration, that > is). So, you're better off using small vtapes. Because if it only > writes 5 GB to 150 GB in a 2 TB NAS, that remaining 145 GB is > unavailable to Amanda until that vtape comes up for overwriting. > Perhaps I misunderstand Winston's comment here. But if you write 5GB to a "150GB" vtape, the "remaining 145GB" are available for other vtapes. My 240 x 100GB vtapes (nominally 24TB) are on 20TB of disk. None of the six disks are over 80% full. jon -- Jon H. LaBadie j...@jgcomp.com 11226 South Shore Rd. (703) 787-0688 (H) Reston, VA 20190 (703) 935-6720 (C)
