After upgrading from 3.0 to 3.1, some custom config to rename NICs is not working.
Custom config commands, such as this, were used on XEN hypervisors to ensure NIC naming is permanent.
echo -e 'DEVICE=app1\nHWADDR=90:E2:BA:2B:4F:0D'>>/etc/sysconfig/network-scripts/ifcfg-app1
In version 3.1 and later, all cloudboot server NICs are set to 'up' after the server is booted. Now, the ifup command will fail because the MAC conflicts with an interface that is already up.
Please replace the custom config commands so they are similar to this example:
nic0=`ifconfig -a | grep 90:E2:BA:2B:4F:0D | cut -f1 -d " " ` && ip link set $nic0 down && ip link set $nic0 name app1 && ip link set app1 up