[pkg-dhcp-devel] Bug#717217: DHCP: 5 bad udp checksums in 5 packets

[Izzy Blacklock]

Having the same problem here.

Found adding the following iptables rule to the dhcp server (dnsmasq on 
debian wheeze) seems to fix the problem.

iptables -A POSTROUTING -t mangle -p udp --dport bootpc -j CHECKSUM 
--checksum-fill

Got the info from the following link:

http://lists.centos.org/pipermail/centos/2013-February/132080.html

Hope this is helpful in resolving the problem permanently.

I believe this issue may also have effected a Canon Color lazer printer 
that suddenly stopped getting addresses via dhcp. I thought I had 
isolated it to a bad switch, but now I'm wondering if this wasn't the 
issue and the new switch was correcting the missing udp checksum?  I 
found that the printer would work if it was connected to a cascaded 
switch, but not if it was connected directly to the main switch - the 
one I thought was bad and replaced with a different model.

...Izzy