Backups with AMANDA
Background
We have two main file-servers (musashi, and yamato), which each perform their own backups Monday through Friday (typically). Musashi has a SCSI-attached HP LTO-1 Ultrium 230 (Aug. 2003) tape-drive; yamato has a replacement Ultrium 232 (Nov. 2006) tape-drive.
Yamato only backs up it's SCSI-connected RAID drives. Musashi doesn't back up one of it's own SCSI-connected RAID drives (too much non-essential data), but musashi does "reach out" and backup other machines' files. What gets backed up is listed/controlled in the /etc/amanda/Dailyxxx/disklist. Both yamato and musashi have amanda configured as a server and client, while the remote machines captured by musashi have amanda configured as a client-only.
Amanda Server Configuration
The first step was to determine the tapetype entry, in /etc/amanda/Dailyxxx/amanda.conf; here are the results from two different tests on separate systems:
Ultrium 230
define tapetype Ultrium230 {
comment "HP Ultrium 230, produced by amtapetype"
length 101376 mbytes
filemark 0 kbytes
speed 13871 kps
}
Ultrium 232
amanda@trainwreck ~ $ amtapetype -f /dev/nst0 -e 100G -o
Writing 1024 Mbyte compresseable data: 37 sec
Writing 1024 Mbyte uncompresseable data: 72 sec
WARNING: Tape drive has hardware compression enabled
Estimated time to write 2 * 102400 Mbyte: 14400 sec = 4 h 0 min
wrote 3080192 32Kb blocks in 94 files in 7025 seconds (short write)
wrote 3096576 32Kb blocks in 189 files in 7511 seconds (short write)
define tapetype unknown-tapetype {
comment "just produced by tapetype prog (hardware compression on)"
length 96512 mbytes
filemark 0 kbytes
speed 13611 kps
}
Tape Drive Compression
Compression can be turned on or off using the mt tool noted below, then initiating the tapetype check; kill the tapetype check with ctrl-C when you've got enough info (takes quite a few minutes)
trainwreck ~ # mt -f /dev/nst0 defcompression 1 trainwreck ~ # su - amanda amanda@trainwreck ~ $ amtapetype -f /dev/nst0 -e 100G -o Writing 1024 Mbyte compresseable data: 42 sec Writing 1024 Mbyte uncompresseable data: 72 sec WARNING: Tape drive has hardware compression enabled Estimated time to write 2 * 102400 Mbyte: 14400 sec = 4 h 0 min amanda@trainwreck ~ $ logout trainwreck ~ # mt -f /dev/nst0 defcompression 0 trainwreck ~ # su - amanda amanda@trainwreck ~ $ amtapetype -f /dev/nst0 -e 100G -o Writing 512 Mbyte compresseable data: 38 sec Writing 512 Mbyte uncompresseable data: 39 sec Estimated time to write 2 * 102400 Mbyte: 15600 sec = 4 h 20 min
Amanda Client Configuration
Unfortunately, with the Gentoo packaging, you get more than you need, for just a client:
inferno / # emerge -pv amanda These are the packages that would be merged, in order: Calculating dependencies... done! [ebuild N ] sys-block/mtx-1.2.18 164 kB [ebuild N ] sci-visualization/gnuplot-4.0-r1 USE="emacs gd png readline -X -doc -ggi -pdf -plotutils (-svga) -xemacs" 2,111 kB [ebuild N ] app-arch/mt-st-0.7-r1 35 kB [ebuild N ] sys-apps/xinetd-2.3.14 USE="perl tcpd" 295 kB [ebuild N ] app-arch/dump-0.4.41 USE="readline -ermt -static" 277 kB [ebuild N ] app-backup/amanda-2.4.5 USE="-berkdb -debug -gdbm -samba -xfs" 1,506 kB Total: 6 packages (6 new), Size of downloads: 4,386 kB
There are a couple of separate steps required, for amanda-client to work - configuring the xinetd meta-server, and configuring amanda. Most aggravations seem to stem from permissions, whether it's the server-access through xinetd, or the amanda-permitted-user in .amandahosts.
inferno / # emacs -nw /etc/xinetd.d/amanda
service amanda
{
socket_type = dgram
protocol = udp
wait = yes
user = amanda
group = amanda
groups = yes
server = /usr/libexec/amandad
# You need to ensure this points to your Amanda server!
# Don't just remove it!
only_from = trainwreck.shaw.ca (clearly, this should point to your server)
disable = no
}
If this is a brand-new installation of xinetd, don't forget to start it! And, add it to your startup-scripts (Gentoo shown):
inferno / # /etc/init.d/xinetd start * Caching service dependencies ... [ ok ] * Starting xinetd ... [ ok ]
And:
inferno / # rc-update add xinetd default * xinetd added to runlevel default
inferno / # emacs -nw /etc/amanda/amandahosts # Machine-name for those hosts which are permitted to back up (fully-qualified # is best). An entry in /etc/hosts adds fail-safe against DNS death :-) # | # | permitted user-name # | | trainwreck.shaw.ca amanda (again, use your server)
That's really all the client needs, unless you're actively using tcpwrappers, in which case /etc/hosts.allow and /etc/hosts.deny may require changes. Similarly, if iptables is running, you'll need to add firewall rules to allow amanda through.
To now bring this client into the backup routine, some entries are needed on the backup-server, in the disklist file:
trainwreck ~ # emacs -nw /etc/amanda/Daily/disklist
Now, run a check from your backup-server, to ensure things look good:
amanda@trainwreck ~ $ amcheck Daily Amanda Tape Server Host Check ----------------------------- Holding disk /holding: 16814560 kB disk space available, that's plenty NOTE: skipping tape-writable test Tape Daily07 label ok NOTE: info dir /usr/local/var/amanda/Daily/curinfo/inferno: does not exist NOTE: it will be created on the next run. Server check took 0.245 seconds Amanda Backup Client Hosts Check -------------------------------- Client check: 2 hosts checked in 10.069 seconds, 0 problems found (brought to you by Amanda 2.4.5)