Note: this bug assumes network_device_mtu is not set on Nova or Neutron.
Was shipped as part of 7.2.0 rebase.
*** Bug 1359951 has been marked as a duplicate of this bug. ***
According to our records, this should be resolved by openstack-neutron-7.2.0-5.el7ost. This build is available now.
According to the with those steps to reproduce the issue happens sometimes I would like to know what is the exactly steps that reproduce the issue so I can verify it ?
During my check its looks like there is no mtu calculation according to tenant network type . on rhos-8 [root@controller-0 ~]# rpm -qa |grep openstack-neutron openstack-neutron-bigswitch-agent-2015.3.8-1.el7ost.noarch openstack-neutron-metering-agent-7.2.0-5.el7ost.noarch openstack-neutron-common-7.2.0-5.el7ost.noarch openstack-neutron-bigswitch-lldp-2015.3.8-1.el7ost.noarch openstack-neutron-ml2-7.2.0-5.el7ost.noarch openstack-neutron-7.2.0-5.el7ost.noarch openstack-neutron-openvswitch-7.2.0-5.el7ost.noarch openstack-neutron-lbaas-7.2.0-1.el7ost.noarch [root@controller-0 ~]# ip net exec qrouter-5d600579-be8e-436b-97c3-9372ccc954b0 ifconfig lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 65 bytes 7280 (7.1 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 65 bytes 7280 (7.1 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 qg-7eede1bc-89: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1400 inet 10.0.0.210 netmask 255.255.255.0 broadcast 10.0.0.255 inet6 fe80::f816:3eff:feb2:dc6d prefixlen 64 scopeid 0x20<link> ether fa:16:3e:b2:dc:6d txqueuelen 1000 (Ethernet) RX packets 257543 bytes 1200729492 (1.1 GiB) RX errors 0 dropped 3 overruns 0 frame 0 TX packets 135410 bytes 2296647603 (2.1 GiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 qr-472db56c-ea: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1400 inet 10.0.5.1 netmask 255.255.255.0 broadcast 10.0.5.255 inet6 fe80::f816:3eff:fee9:304c prefixlen 64 scopeid 0x20<link> ether fa:16:3e:e9:30:4c txqueuelen 1000 (Ethernet) RX packets 137621 bytes 2295022550 (2.1 GiB) RX errors 0 dropped 3 overruns 0 frame 0 TX packets 258581 bytes 1204438626 (1.1 GiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 qr-4819ee8d-3a: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1400 inet6 fe80::f816:3eff:fe62:7f7c prefixlen 64 scopeid 0x20<link> inet6 2005::1 prefixlen 64 scopeid 0x0<global> ether fa:16:3e:62:7f:7c txqueuelen 1000 (Ethernet) RX packets 198 bytes 14630 (14.2 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 1376 bytes 151040 (147.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 qr-778968e8-7e: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1400 inet 10.0.8.1 netmask 255.255.255.0 broadcast 10.0.8.255 inet6 fe80::f816:3eff:fe93:3821 prefixlen 64 scopeid 0x20<link> ether fa:16:3e:93:38:21 txqueuelen 1000 (Ethernet) RX packets 2 bytes 192 (192.0 B) RX errors 0 dropped 3 overruns 0 frame 0 TX packets 10 bytes 864 (864.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 [root@controller-0 ~]# grep mtu /etc/neutron/* /etc/neutron/neutron.conf:advertise_mtu = True /etc/neutron/neutron.conf:network_device_mtu=1400 /etc/neutron/plugin.ini:path_mtu = 0
When network_device_mtu is used, then new MTU calculation mechanism is not utilized, and hence all devices indeed use network_device_mtu values. To validate the bug, you should opt in the new MTU mechanism by unsetting network_device_mtu, and instead setting segment_mtu in plugin.ini (this is the same option as global_physnet_mtu in OSP9+). After you set segment_mtu, unset network_device_mtu, and restart neutron-server, you should see new router legs getting MTUs as calculated by the new mechanism. That being said, one may suggest that the new mechanism should be used in all installations. If you think that's worth pursuing for OSP8 that is released a while ago, then please report a bug against tripleo.
validate according to Ihar steps to reproduce in comment 9 OSP8 [root@controller-0 ~]# rpm -qa |grep openstack-neutron- openstack-neutron-bigswitch-agent-2015.3.8-1.el7ost.noarch openstack-neutron-metering-agent-7.2.0-5.el7ost.noarch openstack-neutron-common-7.2.0-5.el7ost.noarch openstack-neutron-bigswitch-lldp-2015.3.8-1.el7ost.noarch openstack-neutron-ml2-7.2.0-5.el7ost.noarch openstack-neutron-7.2.0-5.el7ost.noarch openstack-neutron-openvswitch-7.2.0-5.el7ost.noarch openstack-neutron-lbaas-7.2.0-1.el7ost.noarch