Public bug reported: On my single node devstack setup, there are 2 VMs hosted. VM1 has no floating IP assigned. VM2 has a floating IP assigned. From VM1, ping to VM2 using the floating IP. Ping output reports the replies comes from VM2's fixed ip address. The reply should be from VM2's floating ip address.
This is a DVR problem as it doesn't happen when the L3 agent's mode is 'legacy'. This may be a problem with the NAT rules defined by the DVR L3-agent. I used the latest neutron code on the master branch to reproduce, The agent_mode is set to 'dvr_snat'. Here is how the problem is reproduced: VM1 and VM2 runs on the same host. VM1 has fixed IP of 10.11.12.4, no floating-ip associated. VM2 has fixed IP of 10.11.12.5 floating-ip=10.127.10.226 Logged into VM1 from the qrouter namespace. >From VM1, ping to 10.127.10.226, ping output at VM1 reports ping replies are from the VM2's fixed IP address # ssh cirros@10.11.12.4 cirros@10.11.12.4's password: $ ping 10.127.10.226 PING 10.127.10.226 (10.127.10.226): 56 data bytes 64 bytes from 10.11.12.5: seq=0 ttl=64 time=4.189 ms 64 bytes from 10.11.12.5: seq=1 ttl=64 time=1.254 ms 64 bytes from 10.11.12.5: seq=2 ttl=64 time=2.386 ms 64 bytes from 10.11.12.5: seq=3 ttl=64 time=2.064 ms ^C --- 10.127.10.226 ping statistics --- 4 packets transmitted, 4 packets received, 0% packet loss round-trip min/avg/max = 1.254/2.473/4.189 ms $ If I associate a floating IP on VM1 then repeat the same test, ping reports the replies comes from VM2's floating IP: # ssh cirros@10.11.12.4 cirros@10.11.12.4's password: $ ping 10.127.10.226 PING 10.127.10.226 (10.127.10.226): 56 data bytes 64 bytes from 10.127.10.226: seq=0 ttl=63 time=16.750 ms 64 bytes from 10.127.10.226: seq=1 ttl=63 time=2.417 ms 64 bytes from 10.127.10.226: seq=2 ttl=63 time=1.558 ms 64 bytes from 10.127.10.226: seq=3 ttl=63 time=1.042 ms 64 bytes from 10.127.10.226: seq=4 ttl=63 time=2.770 ms ^C --- 10.127.10.226 ping statistics --- 5 packets transmitted, 5 packets received, 0% packet loss round-trip min/avg/max = 1.042/4.907/16.750 ms $ ** Affects: neutron Importance: Undecided Status: New -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1462154 Title: With DVR Pings to floating IPs replied with fixed-ips Status in OpenStack Neutron (virtual network service): New Bug description: On my single node devstack setup, there are 2 VMs hosted. VM1 has no floating IP assigned. VM2 has a floating IP assigned. From VM1, ping to VM2 using the floating IP. Ping output reports the replies comes from VM2's fixed ip address. The reply should be from VM2's floating ip address. This is a DVR problem as it doesn't happen when the L3 agent's mode is 'legacy'. This may be a problem with the NAT rules defined by the DVR L3-agent. I used the latest neutron code on the master branch to reproduce, The agent_mode is set to 'dvr_snat'. Here is how the problem is reproduced: VM1 and VM2 runs on the same host. VM1 has fixed IP of 10.11.12.4, no floating-ip associated. VM2 has fixed IP of 10.11.12.5 floating-ip=10.127.10.226 Logged into VM1 from the qrouter namespace. From VM1, ping to 10.127.10.226, ping output at VM1 reports ping replies are from the VM2's fixed IP address # ssh cirros@10.11.12.4 cirros@10.11.12.4's password: $ ping 10.127.10.226 PING 10.127.10.226 (10.127.10.226): 56 data bytes 64 bytes from 10.11.12.5: seq=0 ttl=64 time=4.189 ms 64 bytes from 10.11.12.5: seq=1 ttl=64 time=1.254 ms 64 bytes from 10.11.12.5: seq=2 ttl=64 time=2.386 ms 64 bytes from 10.11.12.5: seq=3 ttl=64 time=2.064 ms ^C --- 10.127.10.226 ping statistics --- 4 packets transmitted, 4 packets received, 0% packet loss round-trip min/avg/max = 1.254/2.473/4.189 ms $ If I associate a floating IP on VM1 then repeat the same test, ping reports the replies comes from VM2's floating IP: # ssh cirros@10.11.12.4 cirros@10.11.12.4's password: $ ping 10.127.10.226 PING 10.127.10.226 (10.127.10.226): 56 data bytes 64 bytes from 10.127.10.226: seq=0 ttl=63 time=16.750 ms 64 bytes from 10.127.10.226: seq=1 ttl=63 time=2.417 ms 64 bytes from 10.127.10.226: seq=2 ttl=63 time=1.558 ms 64 bytes from 10.127.10.226: seq=3 ttl=63 time=1.042 ms 64 bytes from 10.127.10.226: seq=4 ttl=63 time=2.770 ms ^C --- 10.127.10.226 ping statistics --- 5 packets transmitted, 5 packets received, 0% packet loss round-trip min/avg/max = 1.042/4.907/16.750 ms $ To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1462154/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp