[linux-lvm] LVM VG is not activated during system boot

[MegaBrutal]

Now I think I figured out what's going on. It seems to be
Debian/Ubuntu specific, but I post here, maybe Debian/Ubuntu devs are
here and see this.

Bug report:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1396213

What actually makes the VG activation so long is that I have a
snapshot. Activating the snapshot takes very long, and bringing up the
entire VG takes about 5 minutes. This wouldn't be such a big problem,
as I could just patiently wait for the activation (with rootdelay).
But it seems something (maybe some kind of watchdog) kills vgchange
before it could finish bringing up all VGs. I had the fortune to boot
a developmental Vivid, and I've seen some 'watershed' messages stating
that 'vgchange' was killed because it was taking "too long". If we'd
let 'vgchange' to finish properly, I had the 2nd VG activated
properly, which contains my root FS.

It's a server. If it has a long boot time, so be it, it doesn't get
rebooted often anyway during normal circumstances. But it is required
to boot up without user interaction, e.g., when I issue a reboot
remotely. The main problem is that currently, user interaction is
necessary to pass initrd (as the root VG needs to be manually
activated), which means, I can only reboot the server when I'm
physically near.


2014-11-25 18:00 GMT+01:00 MegaBrutal <megabrutal at gmail.com>:
>
> No, I don't have such kernel option.
>
> But previously it was working without that. Aren't all volume groups
> supposed to auto-activate, unless I set otherwise in lvm.conf?
>
> I'll try this kernel option, however.
>
> I have a "rootdelay" set to make initrd wait longer for the boot
> device. With previous kernels, it worked, but now no matter how long I
> set this value, the VG never activates. It only activates when I
> manually activate it from the initrd prompt.
>
>
> 2014-11-25 17:15 GMT+01:00 Daniel Savard <daniel.savard at gmail.com>:
> > What are your kernel boot options? Do you specify the VGs you wish to
> > be activated at boot time there?
> >
> > I have one entry like this one for each VG: rd.lvm.vg=vgname
> > -----------------
> > Daniel Savard
> >
> >
> > 2014-11-25 10:54 GMT-05:00 MegaBrutal <megabrutal at gmail.com>:
> >> 2014-11-25 15:33 GMT+01:00 Peter Rajnoha <prajnoha at redhat.com>:
> >>> On 11/25/2014 03:19 PM, MegaBrutal wrote:
> >>>> 2014-11-25 9:01 GMT+01:00 Peter Rajnoha <prajnoha at redhat.com
> >>>> <mailto:prajnoha at redhat.com>>:
> >>>>
> >>>>     What's the exact lvm2 version used (lvm --version)?
> >>>>
> >>>>
> >>>> root at vmhost:~# lvm version
> >>>>   LVM version:     2.02.98(2) (2012-10-15)
> >>>>   Library version: 1.02.77 (2012-10-15)
> >>>>   Driver version:  4.27.0
> >>>>
> >>>>
> >>>>
> >>>>     Is lvmetad enabled in your setup? (global/use_lvmetad=1 setting
> >>>>     in lvm.conf and lvmetad daemon running?)
> >>>>
> >>>>
> >>>>     use_lvmetad = 0
> >>>>
> >>>> No such daemon is running.
> >>>
> >>> This means that LV autoactivation is not enabled in that case too
> >>> (as it depends on lvmetad to be active) and there must a direct
> >>> call for the activation (vgchange/lvchange -ay/-aay)
> >>>
> >>> However, most distributions do not use lvmetad in initrd anyway
> >>> (the only I know of at the moment is Arch Linux). As such, I think
> >>> this is a problem with distribution's initrd that is not waiting
> >>> properly for all PVs to show up and it calls LV activation prematurely.
> >>> I'd report your issue to your distribution's initrd component as each
> >>> distribution uses its own initrd scheme (I could help you with Fedora's
> >>> dracut initrd, but I don't see into Debian's/Ubuntu initrd scheme).
> >>>
> >>>>
> >>>>
> >>>>
> >>>>     Does it activate when you run vgchange -aay vmdata-vg vmhost-vg
> >>>>     directly on the busybox cmd line?
> >>>>
> >>>>
> >>>> The exact command I used to use in the BusyBox prompt is
> >>>> lvm vgchange -ay vmhost-vg
> >>>>
> >>>> Or, if I remember correctly, it activates simply by
> >>>> lvm vgchange -ay
> >>>> as well.
> >>>>
> >>>> Then I exit the BusyBox prompt, and the boot process continues correctly.
> >>>>
> >>>> My root FS is in vmhost-vg, and I have no idea why it doesn't come up
> >>>> automatically.
> >>>
> >>> Yeah, it all points to premature vgchange call in initrd's script.
> >>> Please, report this in your distribution's bug tracking system if
> >>> possible.
> >>
> >> Thanks for the advice!
> >> I opened a Launchpad report here:
> >> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1396213