How to migrate a regular LXC container to a Proxmox LXC container?

Solution 1:

Without detailed explanation here is how you can do this.

1. Create an archive of your LXC container.
2. Create a Proxmox Container using that archive as a template.

First cd into your lxc container root directory:

cd /var/lib/lxc/debian8/rootfs/

(If you used an lvm volume as your containers storage, you need to mount it and cd into your mount point, which can be done by mount /dev/mapper/<lvgroup-lvdisk> /var/lib/lxc/debian8/rootfs/, and than cd into the mount point)

Create an archive:

tar -czvf /var/lib/vz/template/cache/my_debian8_template.tar.gz ./

Then create a new proxmox container out of that

pct create 100 /var/lib/vz/template/cache/my_debian8_template.tar.gz \
    -description LXC -hostname pvecontainer01 -memory 1024 -nameserver 8.8.8.8 \
    -net0 name=eth0,hwaddr=52:4A:5E:26:58:D8,ip=192.168.15.147/24,gw=192.168.15.1,bridge=vmbr0 \
    -storage local -password changeme

(You can modify your options as you would like.)

For more information see - man pct

Solution 2:

still valid question and answer, but since time passed it need an update. Proxmox v6 allows you to create unprivileged container (by default), and since is, uhm, unprivileged (more about unprivileged CT on their wiki), you're unable to create devices or sockets (it is possible by manually editing config, but not a subject of this post)

That is why you may possibly need to exclude special dirs like sys, proc, net or dev from container backup.

So the command would rather be this:

tar --exclude=dev --exclude=sys --exclude=proc -czvf /var/lib/vz/template/cache/my_debian8_template.tar.gz ./

or you will get many kinds of "permission denied" restoring container.