Monthly Archives: December 2016

Modifying a Proxmox LXC container

By   December 23, 2016

I was introduced to the awesomeness that is Proxmox VE and got down to convering my old virtual server to Proxmox VM’s… Along the way I decided some of my VM’s didn’t need to be VM’s but that LXC containers would be just fine.  After making my second container, I got tired of running the same handful of commands (create a user account, git clone my dotfiles, install tmux, etc) so decided to investigate modifying the Ubuntu 16.04 template.  This turns out to be very easy using ‘vzdump’.

 

So here’s another “memo to self”.

First build a container, set it up the way you want it, then use vzdump to create a tarball of it.  Copy it to your templates directory and you’re done:

cd <container template dir>
vzdump -dumpdir . 102
gzip vzdump-lxc-102-2016_12_23-07_53_55.tar
mv vzdump-lxc-102-2016_12_23-07_53_55.tar.gz ubuntu-16.04-mpv_1604-1_amd64.tar.gz

NFS client mount within a Proxmox LXC container.

By   December 23, 2016

Another “memo to self” …

 

[ Edit: minor change for Proxmox 5.x at bottom]

Having trouble doing an NFS mount from within a Proxmox LXC container?  A google search took me here and it pretty much answers the question but doesn’t work with Proxmox 4.4-1.  The error I was seeing after following the advice in the above was:

apparmor="STATUS" operation="profile_replace" profile="unconfined" name="lxc-container-default-cgns" pid=11339 comm="apparmor_parser"

So you also need to edit /etc/apparmod.d/lxc/lxc-container-default-cgns and make it look like so:

# Do not load this file. Rather, load /etc/apparmor.d/lxc-containers, which
# will source all profiles under /etc/apparmor.d/lxc

profile lxc-container-default-cgns flags=(attach_disconnected,mediate_deleted) {
 #include <abstractions/lxc/container-base>

# the container may never be allowed to mount devpts. If it does, it
 # will remount the host's devpts. We could allow it to do it with
 # the newinstance option (but, right now, we don't).
 deny mount fstype=devpts,
 mount fstype=nfs,
 mount fstype=cgroup -> /sys/fs/cgroup/**,
}

and then subsequently do:

service apparmor reload

Edit: On proxmox 5.2-1 the file is /etc/apparmor.d/lxc/lxc-default-cgns.  The rest of the above is still correct.