[Lxc-users] Fun kernel problem: garbled /var/log/kern.log, can't create hard link to particular file in /usr/bin

[Serge Hallyn]

Quoting Dan Kegel (dank at kegel.com):
> There I was, minding my own business, running stock lxc on ubuntu 12.04,
> when suddenly I couldn't install a perl update inside the container.
> Turned out to be it couldn't create a hard link to /usr/bin/s2p
> (though it could to /usr/bin/yes):
> 
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ sudo ln /usr/bin/yes
> /usr/bin/yes.foo
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ ls -l /usr/bin/yes
> -rwxr-xr-x 2 root root 22912 Nov 19 22:25 /usr/bin/yes
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ ls -l /usr/bin/s2p
> -rwxr-xr-x 1 root root 53327 Nov 27 00:50 /usr/bin/s2p
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ sudo ln /usr/bin/s2p
> /usr/bin/s2p.foo
> ln: failed to create hard link `/usr/bin/s2p.foo' => `/usr/bin/s2p':
> No such file or directory
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ cp /usr/bin/s2p /tmp
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ sudo ln -s
> /usr/bin/s2p /usr/bin/s2p.foo
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ sudo rm !$
> sudo rm /usr/bin/s2p.foo
> buildbot at testbot01-ubu1204-temp-g-speak-unique:~$ sudo ln
> /usr/bin/s2p /usr/bin/s2p.foo
> ln: failed to create hard link `/usr/bin/s2p.foo' => `/usr/bin/s2p':
> No such file or directory

Hi,

this is an ephemeral container right?  Yeah we've had issues with
overlayfs - which may or may not be exacerbated by apparmor - in
precise for a long time.  They seem to go away occasionally, but
always seem to come back :(  And they usually seem to manifest
during package upgrades.