fstab doesn't work for lvm based containers

[Serge Hallyn]

The entries in /var/lib/lxc/<container>/fstab are always created relative to a full path, i.e.

proc /var/lib/lxc/p1/rootfs/proc proc nodev,noexec,nosuid 0 0

A check is made in src/lxc/conf.c:mount_entry_on_absolute_rootfs() that the path starts with the containers rootfs path - but that path is a block device for lvm containers.

The simplest solution is to have our templates create the entries with relative pathnames (relative to the container's '/') in the form:

proc proc proc nodev,noexec,nosuid 0 0

[Serge Hallyn (serge-hallyn)]

To be clear, this worked ok before because the container would mount proc and sys itself. Now that apparmor forbids that, this breaks lvm backed containers.

[Serge Hallyn (serge-hallyn)]

Note that while using relative pathnames is fine going forward, it doesn't help people with existing containers. Perhaps the next package upgrade should convert existing containers to remove relative paths?

[Launchpad Janitor (janitor)]

This bug was fixed in the package lxc - 0.7.5-3ubuntu41

---------------
lxc (0.7.5-3ubuntu41) precise; urgency=low

  * add lxc-shutdown command:
    - 0060-lxc-shutdown: add the command to the source
    - debian/lxc.upstart: use lxc-shutdown to shut down containers cleanly
    - debian/lxc.default: add LXC_SHUTDOWN_TIMEOUT (default 120s)
  * support per-container apparmor policies: (LP: #953453)
    - 0061-lxc-start-apparmor: add lxc.aa_profile to config file. If not
      specified, lxc-default profile is used for container. Otherwise, the
      specified profile is used.
      Note that per-container profiles must be named 'lxc-*'.
    - split debian/lxc-default.apparmor from debian/lxc.apparmor.
    - have /etc/apparmor.d/lxc-containers #include /etc/apparmor.d/lxc/*
    - debian/lxc.postinst: load the new lxc-containers profiles
    - debian/lxc.postrm: remove lxc-containers profiles
    - debian/rules: make new etc/apparmor.d/lxc dir and copy lxc-default into it
    - debian/control: add libapparmor-dev to build-depends
    - debian/lxc.upstart: load apparmor per-container policies at pre-start.
  * debian/lxc.apparmor: insert the stricter mount rules for lxc-start
    (LP: #645625) (LP: #942934)
  * debian/local/lxc-start-ephemeral: re-enable aufs option (LP: #960262)
  * replace upstream lxc-wait with our own bash script (LP: #951181)
    - debian/local/lxc-wait: the script
    - debian/rules: copy the script into place
  * 0062-templates-relative-paths: update templates to use relative paths,
    and make lxc-start always accept /var/lib/lxc/CN/rootfs as target prefix,
    to make lvm containers work. (LP: #960860)
 -- Serge Hallyn <email address hidden> Wed, 21 Mar 2012 08:20:06 -0500