[CentOS-virt] Can't build 5.9 with KVM on a 6.3 host - DHCP hang?

[Stephen Harris]

During the build (via a serial console) we get
  input: ImExPS/2 Generic Explorer Mouse as /class/input/input1
  running install...
  running /sbin/loader
  Sending request for IP information for eth0...
  Determining host name and domain...
  Sending request for IP information for eth0...
  Determining host name and domain...

And there it hangs.

On the 6.3 host:
  Feb  8 08:28:55 penfold dhcpd: DHCPDISCOVER from 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPOFFER on 10.0.0.205 to 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPREQUEST for 10.0.0.205 (10.0.0.134) from 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPACK on 10.0.0.205 to 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPDISCOVER from 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPOFFER on 10.0.0.205 to 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPREQUEST for 10.0.0.205 (10.0.0.134) from 52:54:00:5a:a7:48 via br0
  Feb  8 08:28:56 penfold dhcpd: DHCPACK on 10.0.0.205 to 52:54:00:5a:a7:48 via br0


I wonder if this could be related to the "renew" problem I'm seeing on
a pre-existing 5.9 machine:

  Feb  8 07:00:11 mercury dhclient: DHCPREQUEST on eth0 to 10.0.0.134 port 67 (xid=0x4e88b5e5)
  Feb  8 07:00:55 mercury dhclient: DHCPREQUEST on eth0 to 10.0.0.134 port 67 (xid=0x4e88b5e5)
  Feb  8 07:00:55 mercury dhclient: 5 bad udp checksums in 5 packets
  Feb  8 07:01:02 mercury dhclient: DHCPREQUEST on eth0 to 10.0.0.134 port 67 (xid=0x4e88b5e5)
  Feb  8 07:01:14 mercury dhclient: DHCPREQUEST on eth0 to 10.0.0.134 port 67 (xid=0x4e88b5e5)
  Feb  8 07:01:49 mercury dhclient: 5 bad udp checksums in 5 packets

It eventually gets there...
  Feb  8 07:02:00 mercury dhclient: DHCPREQUEST on eth0 to 10.0.0.134 port 67 (xid=0x4e88b5e5)
  Feb  8 07:02:00 mercury dhclient: DHCPACK from 10.0.0.134 (xid=0x4e88b5e5)
  Feb  8 07:02:00 mercury dhclient: bound to 10.0.0.135 -- renewal in 18554 seconds.

My 6.3 new builds work just perfect; it's only 5.x that has problems!

Any ideas?

-- 

rgds
Stephen