On Thu, Nov 24, 2011 at 11:16:10AM +1300, Roger Littin wrote: > Hi Wang, > > I have had similar problems where the director thinks the packet size is > larger than mtu of the real > server and sends back this message. Do you see anything in wireshark to > indicate this. Overly > large udp packet size? > > I think when the network layer hands off the packet to lvs, it may have > already reassembled any > fragments and then when lvs hands it back to the network layer, it is > rejected because it is too > large.
Hi Roger, if you are seeing that problem then I suggest turning off both GRO and LRO on the interface on the director that receives the packets. e.g. # ethtool -k eth0 | egrep '(receive-offload)' generic-receive-offload: on large-receive-offload: on # ethtool -K eth0 lro off # ethtool -K eth0 gro off # ethtool -k eth0 | egrep '(receive-offload)' generic-receive-offload: off large-receive-offload: off IPVS may be used in conjunction with GRO since 2.6.39, so it should not be necessary to disable GRO if a 2.6.39 is used. IPVS is not compatible with LRO as of 3.1 (or 3.2, when it is released) LRO is specific to TCP. GRO affects both TCP and UDP (and other protocols IIRC). _______________________________________________ Please read the documentation before posting - it's available at: http://www.linuxvirtualserver.org/ LinuxVirtualServer.org mailing list - [email protected] Send requests to [email protected] or go to http://lists.graemef.net/mailman/listinfo/lvs-users
