Author: Kjetil Torgrim Homme <kjetilho AT linpro DOT no>
Date: Wed, 19 Sep 2012 00:02:23 +0200
in Linux, you can configure your tape drive to accept variable block size with "mt setblk 0". without a variable block size, I have found that you need to set minimum and maximum block size to the sa
Hello List this has been discussed already some times on the list but as i have ssen no real conclusion i will ask for opinion again. The setup is Bacula 5.2.10 on Ubuntu 12.04 LTS (x64) with a LTO-4
Author: Nils Juergens <nils+bacula AT muon DOT de>
Date: Mon, 20 Aug 2012 18:04:19 +0200
Hello Andreas, Am 20.08.2012 17:29, schrieb lst_hoe02 AT kwsoft DOT de:> As the tape is altering speed all the time with Bacula i would like to for me (with LTO-3) increasing Maximum block size has h
Test the speed of writing to/from disk as well as your tape speeds. SSDs have high IOPS/seek rates but they're not always as fast for sequential operations as you might expect. -- Live Security Virtu
Zitat von Nils Juergens <nils+bacula AT muon DOT de>: Would really nice indeed. As far as i understand the block size used as default (and max.) if nothing is specified is 64,512 Bytes. This looks a
Zitat von Alan Brown <ajb2 AT mssl.ucl.ac DOT uk>: That's why i have done the "dd" tests from the same "disk" which yield the 140MBytes/sec. Other tests with hdparm/bonnie and simple cp yield to some
Zitat von lst_hoe02 AT kwsoft DOT de: Some short tests with the "Maximum Block Size" set, show transfer speed to the LTO-4 of 87MBytes/sec with 256K and 98MBytes/sec with 1M with Bacula encrypted dat
I'm not a dev, however I use 2Mb block size (this is the largest bacula currently supports) The only downside is that you _must_ mark all active tapes as "used" before changing block size. Bacula wil
Zitat von Alan Brown <ajb2 AT mssl.ucl.ac DOT uk>: So i still wonder why the manual recommend not to change this value? The problem of not mixing the blocksize is obvious so if there is not other dow
Because some (older) drive types don't like it and will break. It's only obvious to those experienced with tape. Inexperienced admins are likely to end up with non-restorable tapes due to mixed block
Zitat von Alan Brown <ajb2 AT mssl.ucl.ac DOT uk>: Of course but the manual as far as i understand explicitely discourage altering the value for Block Size with modern hardware: "On most modern tape
That's on the basis that 64k is universal. Some older drives can't even handle blocks this big. Not very many. The vast majority of bacula installations use disk volumes, not tape - which is why debu
Zitat von Alan Brown <ajb2 AT mssl.ucl.ac DOT uk>: I always wonder how they handle offsite backup for disaster recovery... Maybe the plan is simply to go bankrupt in case of fire/water and so on ;-)
Author: Sven Tegethoff <tegethoff AT udobaer DOT de>
Date: Tue, 21 Aug 2012 16:40:57 +0200
At my previous company, we used to do a primary backup on a local backup server, and then copied it over a 100mbit WAN line to a secondary offsite server at a colocation center over the course of the
I suspect I'm an edge case with tape. I'm using old technology and old hardware. That's what I can afford on a home network. I wasn't sure what block size I'm using on my DLT-7000 tape library, but I
Zitat von Sven Tegethoff <tegethoff AT udobaer DOT de>: True, but you first need at least a 100mbit line to something some distance away from the building. We also use B2D for daily backups but have
What you want to know is how big it can go - and the only way to know that is to experiment. Assuming your DLTs are DLT8000, 12 hours is about spot-on for the raw capacity and speed of the tape (40GB
Zitat von Alan Brown <ajb2 AT mssl.ucl.ac DOT uk>: We plan to takle this one with parallel running jobs doing spooling to SSD and despooling to tape. As far as i understand spooling/despooling can ha
In my case, DLT7000. All my backups are in my basement. Including the tapes. I really should move the latest full backups somewhere else. -- Dan Langille http://langille.org/ -- Live Security Virtual
Zitat von Dan Langille <dan AT langille DOT org>: That's around 2MByte/sec? Even DLT-7000 should do better, according to wikipedia it should be able to do around 5MByte/sec. BTW: Do you need some Har