Chris, Thanks for your input.
I am using a 38 slot StorEdge C4 unit and one LTO2 tape drive. See some answers below. I just was looking to see if this is or could be done and if so how. With the virtual tape array maybe this will be mute. Robert _____________________________________________________________________ Robert P. McGraw, Jr. Manager, Computer System EMAIL: rmcg...@purdue.edu Purdue University ROOM: MATH-807 Department of Mathematics PHONE: (765) 494-6055 150 N. University Street West Lafayette, IN 47907-2067 > -----Original Message----- > From: owner-amanda-us...@amanda.org [mailto:owner-amanda- > us...@amanda.org] On Behalf Of Chris Hoogendyk > Sent: Thursday, May 14, 2009 12:53 PM > To: amanda-users@amanda.org > Subject: Re: Amanda and dual tape libraries. > > > > > McGraw, Robert P wrote: > > I have a tape library (38) unit with one lto2 tape unit and one empty > > tape slot. > > > > I need to speed up our backups. > > > > One option is to purchase a second tape unit but not sure how Amanda > > works with a two tape drives. I searched the wiki for information but > > did not get any hits. > > > > I am going to upgrade to the latest Amanda version so the version > should > > not be a problem. > > > > Can Amanda use multiple tape drives for a backup? I want to put > complete > > backup files on a tape and not strip the tapes. > > If you are looking for speed and thinking of upgrading, then why not > get > an LTO4 drive to put in your library and switch to that? Assuming your > backup system can drive it at full speed, that would be 3 times as fast > as the LTO2 drive and would be able to read the LTO2 tapes. Of course, > it would require transitioning to LTO4 tapes, but that's going to give > you 4 times the capacity. [McGraw, Robert P] I had looked into going to an lto4 but I am told by Sun that it is not supported on the C4. It does support the LTO3 but with the small increase of performance and the cost of LTO3 tapes I have decided to stay with the LTO2 for now. > > Another option is larger holding disks (or a holding array), backing > everything to there on its way to the tape. [McGraw, Robert P] I have 500GB and seem to be plenty. I am planning on upgrading to Amanda 2.6.1 this month and start using the flush-threshold-dumped parameters. This should help. Also this summer I will have access to a 8TB array and will set up virtual tapes on this which will help. > > Do your backup reports indicate that the taping speed is the > bottleneck? [McGraw, Robert P] My tape write speed is very close to the max for the LTO unit. > > My library is AIT5, which isn't as fast as LTO. When a DLE is being > written to tape, my system can drive the tape at full speed. However, > the tape drive spends a lot of time idle, as the bottleneck on my > system > is traffic over the network and the busyness of the other servers that > are being backed up. I have large enough spool drives that the backup > activity is going to until it accumulates and is ready for taping. > > > -- > --------------- > > Chris Hoogendyk > > - > O__ ---- Systems Administrator > c/ /'_ --- Biology & Geology Departments > (*) \(*) -- 140 Morrill Science Center > ~~~~~~~~~~ - University of Massachusetts, Amherst > > <hoogen...@bio.umass.edu> > > --------------- > > Erdös 4 > >