LinuxQuestions.org - iSCSI on Ubuntu: working around boot order problems

Hi everyone

I am currently working towards a stable iSCSI connection between Ubuntu server edition (testing with 64bit 8.04.3 LTS and 9.04) and a QNAP TS-291P.

A good basic set of instructions for iSCSI on Ubuntu 9.04 (which also works for 8.04) may be found on HowToForge.com.

During my testing I hit on the following Bug: boot order wrong for iscsi.
The last few postings of this thread claim that the bug was solved. However, my tests indicate the opposite!

The problem is that the open-iscsi daemon and the resulting iSCSI connections are started before the network is started. This setup must fail since iSCSI is a network protocol.

The easy part of the fix is moving the init script for open-iscsi further down in the boot order (as indicated by the valuable posting #15 of the aforementioned bug report):

Code:

mv /etc/rcS.d/S25open-iscsi /etc/rcS.d/S42open-iscsi

After this modification a pre-configured connection to an iSCSI target will be established reliably during startup.

The problem, however, is the shutdown procedure.

This is the relevant excerpt from /etc/init.d/open-iscsi:

Code:

stoptargets() {

        log_daemon_msg "Disconnecting iSCSI targets"

        sync

        # only logout if daemon is running, iscsiadm hangs otherwise

        if [ -s $PIDFILE ] && kill -0 `head -1 $PIDFILE` >/dev/null ; then

                $ADM -m node --logoutall=all

        fi



        log_end_msg 0

}

The crucial line is:

$ADM -m node --logoutall=all

where $ADM is replaced by iscsiadm.
This instruction doesn't seem to work!
I also tried executing the instruction manually at the command prompt. It doesn't work either.

If, however, I explicitely logout from my QNAP iSCSI target like so:

Code:

iscsiadm -m node --targetname "xxxxxxxx" --portal "xxx.xxx.xxx.xxx" --logout

the logout works perfectly.

I also introduced the explicit logout command into /etc/init.d/open-iscsi:

Code:

stoptargets() {

        log_daemon_msg "Disconnecting iSCSI targets"

        sync

        # only logout if daemon is running, iscsiadm hangs otherwise

        if [ -s $PIDFILE ] && kill -0 `head -1 $PIDFILE` >/dev/null ; then

                iscsiadm -m node --targetname "xxxxxxxx" --portal "xxx.xxx.xxx.xxx" --logout

                $ADM -m node --logoutall=all

        fi



        log_end_msg 0

}

This works, too.

Does anyone know, what the problem with the --logoutall=all command might be?
Why doesn't it work?

I'm grateful for your contributions. Thanks in advance. :hattip: