On Tue, 2012-09-04 at 15:08 -0600, Pete Ashdown wrote: > The problem I'm getting is that the reply comes back from the wrong > source with the real IP address of A, B, or C, with the "unexpected > source" error.
This is not caused by IPVS. The solution is that your DNS server must UDP bind/connect to the VIP, not the real-server IPs. The problem is caused by how UDP works in the kernel, and how the socket API was designed. The source IP of the UDP reply packet, is choosen by the kernel, via a route table lookup (not based on the incomming packet). This is know as multi-homed host problem. Its consider a userspace implementation problem, see: http://www.spinics.net/lists/netdev/msg207092.html Userspace can use some other socket API calls to fix this. I have implemented a reference implementation here (covers both IPv4 and IPv6): http://www.spinics.net/lists/netdev/msg208236.html https://github.com/netoptimizer/network-testing/blob/master/src/udp_echo.c -- Best regards, Jesper Dangaard Brouer MSc.CS, Sr. Network Kernel Developer at Red Hat Author of http://www.iptv-analyzer.org LinkedIn: http://www.linkedin.com/in/brouer _______________________________________________ Please read the documentation before posting - it's available at: http://www.linuxvirtualserver.org/ LinuxVirtualServer.org mailing list - lvs-users@LinuxVirtualServer.org Send requests to lvs-users-requ...@linuxvirtualserver.org or go to http://lists.graemef.net/mailman/listinfo/lvs-users
