xen-tools needs to add udev file to handle xen network interfaces under gutsy

[Matt Mossholder]

Binary package hint: xen-tools

Gutsy's persistent network interface naming udev rules are causing Xen instances to have a new network interface name each time a DomU is booted. This is because Xen is dynamically generating a MAC for the DomU, and the /etc/udev/rules.d/70-persistent-net.rules file stores the persistent name based on the MAC address. Rules like the following resolve the issue:

SUBSYSTEM=="net", SUBSYSTEMS=="xen", DRIVERS=="vif", ATTRS{nodename}=="device/vif/0", NAME="eth0"
SUBSYSTEM=="net", SUBSYSTEMS=="xen", DRIVERS=="vif", ATTRS{nodename}=="device/vif/1", NAME="eth1"
etc....

I have been adding them to /etc/udev/rules.d/70-persistent-net.rules manually, but they should probably be handled elsewhere.

[Gabriel Bauman (gabrielbauman)]

Same thing happens with a VMWare image when it is cloned. A new MAC address gets generated, the new interface is created by udev, and the old (stale) eth0 sits there for all time. The result is that the newly cloned VM can't access the network until 70-persistent-net.rules is manually fixed.

[Matthew Caron (matt-mattcaron)]

The same thing happens with Virtualbox.

Basically, any VMM which creates a new MAC address will run afoul of this.

For now, I'm just going to remove the persistent rules file on boot.

[Axel Beckert (xtaran)]

This is fixed with at least xen-tools 4.2-1 from 2010 even over reinstallation with the same distribution as the MAC address is based on the MD5 hash of DomU hostname and distribution. I'm hence closing this issue as "Fix Released".