UCS Virtual Machine Manager normally replaces eth0 with a bridge interface to connect virtual machines to a network. This was achieved by two init scripts renaming the physical interface eth0 to peth0 and creating a bridge called eth0, into which the physical interface was connected.

If you configure your own bridges, bonds or VLANs using the UMC or the Univention Configuration Registry variables described above you need to deactivate these scripts by setting the following UCR variables:

# for KVM:
ucr set uvmm/kvm/bridge/autostart=no
# for Xen:
ucr set xen/bridge/interface=none
# After that re-enable the UMC basic setup
ucr unset umc/modules/setup/network/disabled/by

The UVMM profiles need to be updated as well, since the name of the network bridge is stored in them. The following command updates all profiles currently using interface eth0 to use the new bridge br0.

udm uvmm/profile list --filter interface=eth0 |
       sed -ne 's/^DN: //p' |
       xargs -r -n 1 -d '\n' udm uvmm/profile modify --set interface=br0 --dn