lxc-create hanging

[Robert Collins]

Running
sudo lxc-create -n troveclient -t ubuntu -- --bindhome $(whoami) -a i386

is hanging:

lxc-create: No config file specified, using the default config /etc/lxc/default.conf

I've left it for 15+ m with no further output.

ProblemType: Bug
DistroRelease: Ubuntu 13.04
Package: lxc 0.9.0-0ubuntu3
ProcVersionSignature: Ubuntu 3.8.0-23.34-generic 3.8.11
Uname: Linux 3.8.0-23-generic x86_64
ApportVersion: 2.9.2-0ubuntu8
Architecture: amd64
Date: Sat Jun 22 22:29:02 2013
InstallationDate: Installed on 2013-01-13 (159 days ago)
InstallationMedia: Ubuntu-Server 12.10 "Quantal Quetzal" - Release amd64 (20121017.2)
MarkForUpload: True
SourcePackage: lxc
UpgradeStatus: Upgraded to raring on 2013-04-22 (61 days ago)
lxcsyslog:

[Robert Collins (lifeless)]

When I ctrl-C it I get
^CDelete subvolume '/var/lib/lxc/troveclient/rootfs'
lxc-create: aborted

[Serge Hallyn (serge-hallyn)]

Thanks for reporting this bug. Could you please show the results of ps -ef and sudo lsof ?

I gather /var/lib/lxc is a btrfs filesystem? The hang happens before it debootstraps, right? Could you also show the ps -ef while lxc-create is hanging?

[Serge Hallyn (serge-hallyn)]

(Tried to reproduce this in a nested raring container with a btrfs loopback fs mounted under /var/lib/lxc)

[Robert Collins (lifeless)]

ps -ef | pastebinit
http://paste.ubuntu.com/5796412/
sudo lsof
http://paste.ubuntu.com/5796420/

Yes, I see no sign of debootstrap happening

While hung:
ps -ef | pastebinit
http://paste.ubuntu.com/5796427/

[Robert Collins (lifeless)]

Oh and yes, / is btrfs, and /var/lib/lxc is on that fs.

[Serge Hallyn (serge-hallyn)]

Hi,

so I don't know how to explain this, but udevd is holding /run/lock/subsys/lxc-ubuntu. That file is used by the ubuntu lxc template to mutex the ubuntu template cache entries under /var/cache/lxc.

udevd 27323 root 200w REG 0,21 0 1727325 /run/lock/subsys/lxc-ubuntu

root 27323 1 0 Jun16 ? 00:00:02 udevd --daemon

Please kill task 27323, and that should fix this.

Actually now I recall this was a bug in saucy's udev or debootstrap (but I can't recall or find which offhand). I'm pretty sure it should now be fixed, so please flush your container cache and rebuild from scratch (lxc-create ... -- -F).

I'm going to mark this invalid, but if that doesn't fix it and I seem to be wrong, then please do re-open it.

[Serge Hallyn (serge-hallyn)]

Thanks to cjwatson for remembering the actual bug (bug 1182540). WIll mark this a duplicate of that.

[Robert Collins (lifeless)]

Indeed, that worked - thanks. Will everyone upgrading encounter this? If so, perhaps a forced flush on new version runs would be a good idea?

[Serge Hallyn (serge-hallyn)]

Quoting Robert Collins (<email address hidden>):
> *** This bug is a duplicate of bug 1182540 ***
> https://bugs.launchpad.net/bugs/1182540
>
> Indeed, that worked - thanks. Will everyone upgrading encounter this? If
> so, perhaps a forced flush on new version runs would be a good idea?

No, IIUC this was a temporary bug which affected you because you tried
a lxc-create before the bug was fixed in the archive. (You ran it on
Jun 16, it was fixed on Jun 22).

[Robert Collins (lifeless)]

Ok cool - thanks!