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[root@ovz-node1 ~]# chkconfig vz off
 
[root@ovz-node1 ~]# chkconfig vz off
 
[root@ovz-node1 ~]#  
 
[root@ovz-node1 ~]#  
</pre>
 
 
== Live-Switchover with the help of checkpointing ==
 
 
With the help of [[Checkpointing_and_live_migration|checkpointing]] it is possible to do live switchovers.
 
 
<b>Important:</b> although this HOWTO currently describes the use of DRBD 0.7, it is necessary to use DRBD 8 to be able to use this live-switchover feature reliable. Some hints on using OpenVZ Kernel 2.6.18 with DRBD 8 can be found in [http://forum.openvz.org/index.php?t=msg&th=3213&start=0& this thread in the forum].
 
 
The following scripts are written by Thomas Kappelmueller. They should be placed at /root/live-switchover/ on both nodes. To activate the scripts execute the following commands on both nodes:
 
<pre>
 
[root@ovz-node1 ~]# ln -s /root/live-switchover/openvz /etc/init.d/
 
[root@ovz-node1 ~]# ln -s /root/live-switchover/live_switchover.sh /root/bin/
 
[root@ovz-node1 ~]#
 
</pre>
 
 
It is also necessary to replace <code>vz</code> by an adjusted initscript (<code>openvz</code> in this example). So /etc/ha.d/haresources has the following content on both nodes:
 
<pre>
 
ovz-node1 drbddisk::r0 Filesystem::/dev/drbd0::/vz::ext3 openvz MailTo::youremail@yourdomain.tld
 
</pre>
 
 
=== Script cluster_freeze.sh ===
 
<pre>
 
#!/bin/bash
 
#Script by Thomas Kappelmueller
 
#Version 1.0
 
LIVESWITCH_PATH='/vz/cluster/liveswitch'
 
 
if [ -f $LIVESWITCH_PATH ]
 
then
 
        rm -f $LIVESWITCH_PATH
 
fi
 
 
RUNNING_VE=$(vzlist -1)
 
 
for I in $RUNNING_VE
 
do
 
        BOOTLINE=$(cat /etc/sysconfig/vz-scripts/$I.conf | grep -i "^onboot")
 
        if [ $I != 1 -a "$BOOTLINE" = "ONBOOT=\"yes\"" ]
 
        then
 
                vzctl chkpnt $I
 
 
                if [ $? -eq 0 ]
 
                then
 
                        vzctl set $I --onboot no --save
 
                        echo $I >> $LIVESWITCH_PATH
 
                fi
 
        fi
 
done
 
 
exit 0
 
</pre>
 
 
=== Script cluster_unfreeze.sh ===
 
<pre>
 
#!/bin/bash
 
#Script by Thomas Kappelmueller
 
#Version 1.0
 
 
LIVESWITCH_PATH='/vz/cluster/liveswitch'
 
 
if [ -f $LIVESWITCH_PATH ]
 
then
 
        FROZEN_VE=$(cat $LIVESWITCH_PATH)
 
else
 
        exit 1
 
fi
 
 
for I in $FROZEN_VE
 
do
 
        vzctl restore $I
 
 
        if [ $? != 0 ]
 
        then
 
                vzctl start $I
 
        fi
 
 
        vzctl set $I --onboot yes --save
 
done
 
 
rm -f $LIVESWITCH_PATH
 
 
exit 0
 
</pre>
 
 
=== Script live_switchover.sh ===
 
<pre>
 
#!/bin/bash
 
#Script by Thomas Kappelmueller
 
#Version 1.0
 
 
ps -eaf | grep 'vzctl enter' | grep -v 'grep' > /dev/null
 
if [ $? -eq 0 ]
 
then
 
  echo 'vzctl enter is active. please finish before live switchover.'
 
  exit 1
 
fi
 
ps -eaf | grep 'vzctl exec' | grep -v 'grep' > /dev/null
 
if [ $? -eq 0 ]
 
then
 
  echo 'vzctl exec is active. please finish before live switchover.'
 
  exit 1
 
fi
 
echo "Freezing VEs..."
 
/root/live-switchover/cluster_freeze.sh
 
echo "Starting Switchover..."
 
/usr/lib64/heartbeat/hb_standby
 
</pre>
 
 
=== Script openvz ===
 
<pre>
 
#!/bin/bash
 
#
 
# openvz        Startup script for OpenVZ
 
#
 
 
start() {
 
        /etc/init.d/vz start > /dev/null 2>&1
 
        RETVAL=$?
 
        /root/live-switchover/cluster_unfreeze.sh
 
        return $RETVAL
 
}
 
stop() {
 
        /etc/init.d/vz stop > /dev/null 2>&1
 
        RETVAL=$?
 
        return $RETVAL
 
}
 
status() {
 
        /etc/init.d/vz status > /dev/null 2>&1
 
        RETVAL=$?
 
        return $RETVAL
 
}
 
 
# See how we were called.
 
case "$1" in
 
  start)
 
        start
 
        ;;
 
  stop)
 
        stop
 
        ;;
 
  status)
 
        status
 
        ;;
 
  *)
 
        echo $"Usage: openvz {start|stop|status}"
 
        exit 1
 
esac
 
 
exit $RETVAL
 
 
</pre>
 
</pre>
  
 
[[Category: HOWTO]]
 
[[Category: HOWTO]]

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