How to convert bare metal FS to LXC Container?

[jimmyjoe]

I'm just trying out containers in Proxmox 4.4. I have a 1U bare metal I'd like to convert to a container. I've done this with KVM by booting the VM with a cdrom and then using rsync to copy files over from a hard disk/usb stick onto the VM filesystem. I don't see a cdrom boot option for LXC containers.

What's the process for migrating a bare metal host to a container?
Thanks

 

[LnxBil]

Your approach is correct, just create the LXC container at first and sync everything in there with --delete-before.

 

[jimmyjoe]

Thanks. Is there a way to boot the container from ISO ? I like to boot the target with an acquiesced filesystem before doing a sync. Usually there is an option under Hardware > Add > CDROM for this but that doesn't exist for a container.

 

[LnxBil]

Thanks. Is there a way to boot the container from ISO ? I like to boot the target with an acquiesced filesystem before doing a sync. Usually there is an option under Hardware > Add > CDROM for this but that doesn't exist for a container.

Of course not, you do not need that step and it is technically impossible. You are already on the target so to speak. Containers use the kernel of your PVE host, so you just need to rsync the files (pct mount if you're not using ZFS).

 

[jimmyjoe]

`pct mount` is exactly what I needed. Thanks for the explanation.

 

[LnxBil]

Did it work?

 

[jimmyjoe]

yes, thanks


UPDATE: just tried it on a second host today and it worked perfectly.
I mounted the bare metal root fs on /mnt/ssd and then mounted the container rootfs via pct. Commands below if anyone is wondering how to do it.

pct mount 700
cd /var/lib/lxc/700/rootfs/
rsync -av /mnt/ssd/ . --exclude=proc --exclude=sys --exclude=etc --exclude=dev --exclude=etc/fstab --exclude=default/grub --delete

(to chroot into rootfs)
mount -o bind /proc proc
mount -o bind /dev dev
mount -o bind /dev/pts dev/pts/
mount -o bind /sys sys
chroot /var/lib/lxc/700/rootfs /bin/bash