[systemd-devel] Reboot hangs at the very last step

[Frank Steiner]

Andrei Borzenkov wrote

>> Should the mnt-raid2\x2dbackup.mount contain sth. like "After=network.service"?
> 
> Many dependencies are added implicitly and are not present in unit
> definition. Please show output of
> 
> systemctl show -p Before -p After mnt-raid2.mount
> systemctl show -p Before -p After mnt-raid2\\x2dbackup.mount

Indeed the  mnt-raid2\\x2dbackup.mount is missing 
"After=network.target network-online.target"

Additionally I figured out the culprit for the hang: if iscsi device
nodes are created but not removed before network is shutdown, this 
will cause systemd to hang forever. This happens e.g. when you add
an iscsi device manually with iscsiadm and with "...start=manual",
so that it is not caught by "systemctl stop iscsi.service", and reboot
without removing it first.

Something is trying to access the devices in /dev/.... If the shutdown
is delayed for about three minutes (I did so by activating a service that
is required by shutdown.target and does a "ExecStop=sleep 600") then
a timeout occurs and then the server reboots if it reaches the Shutdown Target
afterwards. Can be seen by e.g. starting "pvs" in the debug shell while
the "sleep 600" runs. After about two minutes pvs returns with error
messages about the iscsi device nodes /dev/raid2-iscsi/...

But if Shutdown Target is reached before this timeout happens, the
server will hang forever. I'm not sure when this happens on our
production servers, they should always cleanly shutdown all iscsi 
devices, but maybe this sometimes fails for some reason. I remember that 
I once saw a "could not umount fs blabla, busy" or. sth.

The SuSE support is working on both issues now.

Thanks for your help!

cu,
Frank

-- 
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