On 21.11.2014 11:24, Cedric Bosdonnat wrote:

Hi all,

As an example, the following command

virt-sandbox-service create --network dhcp,source=default --unitfile sshd.service mysshd -i 512

generates a container definition containing these filesystems (in the same order):

<filesystem type='file' accessmode='passthrough'> <source file='/var/lib/libvirt/images/mysshd.raw'/> <target dir='/var/lib/libvirt/filesystems/mysshd'/> </filesystem> <filesystem type='bind' accessmode='passthrough'> <source dir='/var/lib/libvirt/filesystems/mysshd/var'/> <target dir='/var'/> </filesystem>

Since /var/lib/libvirt/filesystems/mysshd contains nothing, the second FS needs the first one to be mounted for the source directory to exist.

The problem comes with lxcContainerResolveSymlinks() being run before any file system is actually mounted. So the container can't be started and we get the following error:

Failed to access '/var/lib/libvirt/filesystems/mysshd/var': No such file or directory

This would work if the symlinks were resolved right before mounting the FS instead of before mounting any of them. Any strong opinion against it?

Correct, it's a libvirt bug. Even with real bare metal, where fstab is evaluated sequentially per line the symlink resolving is done the way you're suggesting. Wanna contribute a patch? Michal