We have a flow that looks like this: priority=1030,icmp6,in_port=4,icmp_type=135,nd_target=xxxx:xxxx:1:d0::1105:3000/124 actions=resubmit(,25)
When neighbor solicitations come in on port 4 (ethernet interface), we can see them in tcpdump as having the correct nd_target, yet the flow's n_byte, and n_packet counters don't increase, and we confirm the packet falls to a lower priority matching flow (that drops). However, if we remove the nd_target field from the match, the solicitation hits the flow as expected, every time. As another wrinkle, while receiving continuous neighbor solicitations, we simply re-add the above flow in a loop, like "while true; do ovs-ofctl add-flow...; done". And without fail, the flow will suddenly instantly be hit (n_byte and n_packet counters increase, VM actually receives solicitation), with no change at all on what's been coming in on the data plane, and no change to the content of the flow set as a whole. For a similar wrinkle, we can also make the flow hit by simply repeatedly running tcpdump on the interface multiple times. Like if port 4 is eth1, we'll just do "tcpdump -enni eth1" multiple times, and the solicitation will be successfully received by VM, counters increase, etc. Any ideas on why this may be? It's seems like a race condition somewhere that is relevant to matching on nd_target. Other info: # ovs-ofctl --version ovs-ofctl (Open vSwitch) 2.5.0 Compiled Sep 15 2016 12:55:18 OpenFlow versions 0x1:0x4 # uname -a Linux <redacted> 3.13.0-106-generic #153-Ubuntu SMP Tue Dec 6 15:44:32 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux # lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 14.04.5 LTS Release: 14.04 Codename: trusty # ethtool -i eth1 driver: igb version: 5.0.5-k firmware-version: 1.67, 0x80000b97, 15.0.28 bus-info: 0000:01:00.1 supports-statistics: yes supports-test: yes supports-eeprom-access: yes supports-register-dump: yes supports-priv-flags: no
_______________________________________________ discuss mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-discuss
