I manage a few virtual Debian (Wheezy) machines that mount an iSCSI volume. These hold websites and mysql data.
The problem is that in the default shutdown sequence, umountiscsi.sh is called before shutting down cherokee (or apache2) and mysql. So the umount fails because the filesystem is busy and the machine doesn't shutdown properly from the CLI, requiring a reset at the VMWare console.
I searched around for the way to adjust the dependency based boot and shutdown sequence and after reading a lot of web and manual pages I finally understood the way to do it.
First edit /etc/init.d/cherokee (or /etc/init.d/apache2) and /etc/init.d/mysql so that the line:
# Required-Stop:
contains umountiscsi.sh
The logic of Required-Stop is that the services named on the line depend on the current service (webserver, database) being stopped first.
Now run:
insserv -d -v umountiscsi.sh
Despite the warnings on the man page that this is too low level, this is the right command to use. It will rebuild the symlinks in the runlevel directories as well as regenerate the files /etc/init.d/.depend.{boot,start,stop} Next time you shutdown, the webserver and database will be shutdown before unmounting the iSCSI volume.
This assumes that the default start and stop sequences expressed in the INIT lines are correct for you. If you have added services manually using update-rc.d at particular runlevels and sequence points then I cannot guarantee that you will get the desired result.
The problem is that in the default shutdown sequence, umountiscsi.sh is called before shutting down cherokee (or apache2) and mysql. So the umount fails because the filesystem is busy and the machine doesn't shutdown properly from the CLI, requiring a reset at the VMWare console.
I searched around for the way to adjust the dependency based boot and shutdown sequence and after reading a lot of web and manual pages I finally understood the way to do it.
First edit /etc/init.d/cherokee (or /etc/init.d/apache2) and /etc/init.d/mysql so that the line:
# Required-Stop:
contains umountiscsi.sh
The logic of Required-Stop is that the services named on the line depend on the current service (webserver, database) being stopped first.
Now run:
insserv -d -v umountiscsi.sh
Despite the warnings on the man page that this is too low level, this is the right command to use. It will rebuild the symlinks in the runlevel directories as well as regenerate the files /etc/init.d/.depend.{boot,start,stop} Next time you shutdown, the webserver and database will be shutdown before unmounting the iSCSI volume.
This assumes that the default start and stop sequences expressed in the INIT lines are correct for you. If you have added services manually using update-rc.d at particular runlevels and sequence points then I cannot guarantee that you will get the desired result.
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