[systemd-devel] hinting systemd about what to do to make a device appear

[Lennart Poettering]

On Fri, 11.09.15 12:45, martin f krafft (madduck at madduck.net) wrote:

> also sprach Lennart Poettering <lennart at poettering.net> [2015-09-11 12:30 +0200]:
> > Do I see this right, this is luks on lvm on drbd? Yuck!
> 
> luks on drbd, and the local volume is on lvm, yes.
> 
> > Which symlink are you looking for? the drbd one?
> 
> Right. /dev/drbd/by-res/backup

Hmm, not sure what is going on there. I don't know drbd. I figure the
next step is to attach gdb to PID, set a break point in
device_process_new() and figure out why systemd doesn't care for the
symlink. There's a loop after calling
udev_device_get_devlinks_list_entry() and it would be interesting to
see if the symlinks pop up there and why systemd doesn't process
them... Maybe the stat() verification step in the loop is actually
what fails here?

I still have the suspicion that drbd does something weird with /dev,
and breaks things there... To detect that one option might be to use
Martin Pitt's fatrace tool on /dev and see what accesses are made to
/dev when the device is supposed to show up.

Lennart

-- 
Lennart Poettering, Red Hat