Date: Tue, 15 Feb 2005 17:36:06 +0100
From: Mario Wolff <mwolff@unix.schubert-gruppe.de>
To: kern@sibbald.com
CC: bacula-devel <bacula-devel@lists.sourceforge.net>
Subject: Re: Using multiple tapedrives as autochanger!
Hi Kern!
Kern Sibbald schrieb:
> Hello,
>
> There is a similar script named ak-mtx-changer.txt in the
> <bacula>/examples/autochangers directory of the source tree. If you feel
> that your script brings something different, then I'll be happy to
> include it in the same directory. If that is the case, please put a
> small note in an email message to me with the script and I'll include it
> (I know you've already sent the script, but it saves me the time of
> searching for it, and I'm sure I've got the right one).
>
> Best regards, Kern
As far as i understood the ak-mtx-changer.txt it's simply a
human-resource-changer!?!
In the past every single server had it's own DDS-3 Tape, since we switch
to a centralized networkbackup all these drives are unused.
Now i took 6 of these drives and placed it in large case on one
scsi-controller. Running bacula with multitape-changer these six drives
are used as one drive with a 6-Slot-Changer!
Regards,
Mario
PS: I've posted a deploy-script (deploy windows-fd from linux, automated
your hints) a few days ago over gmane to the devellist. This message
was never posted and i got no error message. Maybe problem with the size
(Windows-FD was attached!) ???
[pasted the hints once again for Kern!]
Example:
bacula-dir.conf:
# Definition of DDS tape storage device
Storage {
Name = Multitape
#Do not use "localhost" here
Address = mystorage # N.B. Use a fully qualified name here
SDPort = 9103
Password = "strongsecret" # password for Storage daemon
Device = Multitape
Autochanger = yes
Media Type = DDS-3
}
bacula-sd.conf:
Device {
Name = Multitape #
Media Type = DDS-3
Archive Device = /dev/tape
AutomaticMount = yes; # when device opened, read it
AlwaysOpen = yes;
RemovableMedia = yes;
RandomAccess = no;
# That's the magic!!!
Changer Command = "/etc/bacula/scripts/multitape-changer %c %o %S %a %d"
Changer Device = /dev/null
AutoChanger = yes
}
Hints:
- Important to use a virtual name! multidrive-changer will create links!
(Archive Device = /dev/tape)
- It's a bash script not a sh script!
- SD must run as root or the multitape-changer must be called with sudo
to have write permission to the /dev dir!
- the default-config does an umount on tape-change! Don't switch this!
SD has to release the device-file!
- don't use your tapedrives directly anymore! SD does not know that
/dev/tape is /dev/nst0!
- don't remove the sleep 1 after getslot...! Without the sleep you will
get a "Operation not permitted" error!
- only tested with Debian/GNU-Linux-SID
[end of paste]
--------------050209030507060501040304
Content-Type: text/plain;
name="multitape-changer"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline;
filename="multitape-changer"
#!/bin/bash
#
# Bacula interface to use multiple drives as one tape-changer
# Arguments are copied from the mtx-script! Simply exchange
# the scriptname from demo-config
#
# If you set in your Device resource
#
# Changer Command = "path-to-this-script/multitape-changer %c %o %S %a %d"
# you will have the following input to this script:
#
# multitape-changer "changer-device" "command" "slot" "archive-device" "drive-index"
# $1 $2 $3 $4 $5
#
# for example:
#
# multitape-changer /dev/sg0 load 1 /dev/nst0 0 (on a Linux system)
#
# Setup arguments
cmd="$2"
slot=$3
DEVICE=${4:-/dev/tape}
LABELDIR=/etc/bacula/tapelabel # where to find labelfiles
NULLDEVICE=/dev/null # if unmount link to this
SLOT01=/dev/nst0 # first slot
SLOT02=/dev/nst1 # second slot
# simply append more
#get device for a given slotnumber
getdevice(){
myslot=${1:-1}
if [ ${#myslot} -gt 2 ];then exit 1;fi
if [ ${#myslot} -eq 2 ];then
eval echo \$SLOT$myslot
return
else
eval echo \$SLOT0$myslot
return
fi
}
#get name of labelfile for a given slot
getname(){
myslot=${1:-1}
if [ ${#myslot} -gt 2 ];then exit 2;fi
if [ ${#myslot} -eq 2 ];then
echo SLOT$myslot
return
else
echo SLOT0$myslot
return
fi
}
#how many tapes/slots to manage
getslots(){
count=1
while [ "$( getdevice $count )" ];do
count=$[ $count + 1 ]
done
echo $[ $count - 1 ]
return
}
#get slot for a given device-file
getslot(){
device=${1:-$NULLDEVICE}
if [ "$device" = "$NULLDEVICE" ];then
echo -en "0\n"
return
else
count=1
slotdev=$( getdevice $count )
while [ "$slotdev" ]; do
if [ "$slotdev" = "$device" ];then
echo -en "$count\n"
return
fi
count=$[ $count + 1 ]
slotdev=$( getdevice $count )
done
exit 3
fi
}
if test $# -lt 2 ; then
echo "usage: multitape-changer ctl-device command slot archive-device drive"
echo " Insufficient number of arguments arguments given."
echo " Mimimum usage is first two arguments ..."
exit 4
fi
#
# Check for special cases where only 2 arguments are needed,
# all others are a minimum of 3
case $cmd in
loaded)
;;
unload)
;;
list)
;;
slots)
;;
*)
if test $# -lt 3; then
echo "usage: multitape-changer ctl-device command slot archive-device drive"
echo " Insufficient number of arguments arguments given."
echo " Mimimum usage is first three arguments ..."
exit 5
fi
;;
esac
case $cmd in
unload)
if [ -e $DEVICE ];then
rm $DEVICE && ln -s $NULLDEVICE $DEVICE || exit 6
else
ln -s $NULLDEVICE $DEVICE || exit 7
fi
;;
load)
CURDEV=$( getdevice $slot )
if [ -e $DEVICE ];then
rm $DEVICE && ln -s $CURDEV $DEVICE || exit 8
else
ln -s $CURDEV $DEVICE || exit 9
fi
;;
list)
slots=$( getslots )
for slot in $( seq 1 $slots );do
labelfile=$LABELDIR/$( getname $slot )
if [ -f "$labelfile" ];then
echo "$slot:$( head -n 1 $labelfile)"
else
echo "$slot:"
fi
done
exit 0
;;
loaded)
if [ -e $DEVICE ];then
line=$( ls -la $DEVICE )
fi
line=${line:-$NULLDEVICE}
getslot ${line##* }
sleep 1
exit 0
;;
slots)
getslots
exit 0
;;
esac
--------------050209030507060501040304--
