Interface cannot change link addresses - switching IP from one IF to another on a netbooted machine

[Nagy, Attila]

Hi,

I have several netbooted machines, which operate in this way:
- the machine boots up from one interface (PXE, DHCP), for example igb0
- during the boot, an rc script runs* which deletes the IP from igb0 and 
creates the lagg interface with igb0, igb1 etc and sets the original IP 
on that interface (with a statically linked ifconfig)
- normal booting continues from the lagg interface

This has worked for years and broke somewhere in the lifecycle of 10-STABLE.

Now I can't remove the IP address from the interface, ifconfig igb0 
delete gives:
interface igb0 cannot change link addresses!

Any ideas about how could I work around this?

Basically I would like to switch the IP from one interface to another 
while running from an NFS root. (and this has worked before svn rev xxx)

Thanks,