B.10. Could not add rule to fixup DHCP response checksums on network 'default'

Symptom
This message appears:
Could not add rule to fixup DHCP response checksums on network 'default'
Investigation
Although this message appears to be evidence of an error, it is almost always harmless.
Solution
Unless the problem you are experiencing is that the guest virtual machines are unable to acquire IP addresses through DHCP, this message can be ignored.
If this is the case, refer to Section B.8, “PXE Boot (or DHCP) on Guest Failed” for further details on this situation.