Eric Garver: "Most likely you are seeing this bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1488484 It's actually an issue with the kernel GRE driver ignoring IFLA_MTU when the device is created." Creating test package with proposed fix: https://patchwork.ozlabs.org/patch/860192/ ** Changed in: openvswitch (Ubuntu) Status: New => Confirmed ** Changed in: openvswitch (Ubuntu) Importance: Undecided => Critical ** Changed in: neutron Status: New => Invalid ** Bug watch added: Red Hat Bugzilla #1488484 https://bugzilla.redhat.com/show_bug.cgi?id=1488484 -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1742505 Title: gre_sys set to default 1472 when using path_mtu > 1500 with ovs 2.8.x Status in neutron: Invalid Status in openvswitch package in Ubuntu: Confirmed Bug description: Setup: Pike neutron 11.0.2-0ubuntu1.1~cloud0 OVS 2.8.0 Jumbo frames setttings per: https://docs.openstack.org/mitaka/networking-guide/config-mtu.html global_physnet_mtu = 9000 path_mtu = 9000 Symptoms: gre_sys MTU is 1472 Instances with MTUs > 1500 fail to communicate across GRE Temporary Workaround: ifconfig gre_sys MTU 9000 Note: When ovs rebuilds tunnels, such as on a restart, gre_sys MTU is set back to default 1472. Note: downgrading from OVS 2.8.0 to 2.6.1 resolves the issue. Previous behavior: With Ocata or Pike and OVS 2.6.x gre_sys MTU defaults to 65490 It remains at 65490 through restarts. This may be related to some combination of the following changes in OVS which seem to imply MTUs must be set in the ovs database for tunnel interfaces and patches: https://github.com/openvswitch/ovs/commit/8c319e8b73032e06c7dd1832b3b31f8a1189dcd1 https://github.com/openvswitch/ovs/commit/3a414a0a4f1901ba015ec80b917b9fb206f3c74f https://github.com/openvswitch/ovs/blob/6355db7f447c8e83efbd4971cca9265f5e0c8531/datapath/vport-internal_dev.c#L186 To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1742505/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : [email protected] Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp
