Comment 0 for bug 1382054

It would be helpful to be able to create VLAN network interfaces in initrd images provided
by Ubuntu, based on kernel command line parameters. (i.e. VLAN=eth0.100, )

Some use cases for this feature addition are MAAS users trying to boot machines
using a specific VLAN interface.

On a specific case we have 2 physical network interfaces, one is plugged into a specific VLAN interface,
Since we can specify the network interface on BIOS, the initial PXE boot occurs, but
then the installation fails when using the fast-path installer because the specific VLAN is not configured on the ram disk.

While we can use the other network interface because is a trunk interface that allows us to use
several VLANs, this is not supported on all the network architectures and some security limitations doesn't allows this method.

Reference Redhat implementation could be found here:

- http://marc.info/?l=initramfs&m=133767307516594

Reference Suse implementation could be found here:

- https://gitorious.org/opensuse/agrafs-mkinitrd/commit/6124f87f3132b6369c0335c319832619a49d0bf7

The command line syntax for this could be something like, similar to Redhat implementation

        vlan=<vlanname>:<phydevice>

For an example:

        vlan=eth0.2:eth0