Public bug reported: Stale snat namespace on the controller after recovery of dead l3 agent.
Note: Only on Stable/LIBERTY Branch: Setup: Multiple controller (DVR_SNAT) setup. Steps: 1) Create tenant network, subnet and router. 2) Create a external network 3) Attached internal & external network to a router 4) Create VM on above tenant network. 5) Make sure VM can reach outside using CSNAT. 6) Find router hosting l3 agent and stop the l3 agent. 7) Manually move router to other controller (dvr_snat mode). SNAT namespace should be create on new controller node. 8) Start the l3 agent on the controller (the one that stopped in step6) 9) Notice that snat namespace is now available on 2 controller and it is not getting deleted from the agent which is not hosting it. Example: | cfa97c12-b975-4515-86c3-9710c9b88d76 | L3 agent | vm2-ctl2-936 | :-) | True | neutron-l3-agent | | df4ca7c5-9bae-4cfb-bc83-216612b2b378 | L3 agent | vm1-ctl1-936 | :-) | True | neutron-l3-agent | mysql> select * from csnat_l3_agent_bindings; +--------------------------------------+--------------------------------------+---------+------------------+ | router_id | l3_agent_id | host_id | csnat_gw_port_id | +--------------------------------------+--------------------------------------+---------+------------------+ | 0fb68420-9e69-41bb-8a88-8ab53b0faabb | cfa97c12-b975-4515-86c3-9710c9b88d76 | NULL | NULL | +--------------------------------------+--------------------------------------+---------+------------------+ On vm1-ctl1-936 Stale SNAT namespace on Initially hosting controller. ubuntu@vm1-ctl1-936:~/devstack$ sudo ip netns snat-0fb68420-9e69-41bb-8a88-8ab53b0faabb qrouter-0fb68420-9e69-41bb-8a88-8ab53b0faabb On vm2-ctl2-936 (2nd Controller) ubuntu@vm2-ctl2-936:~$ ip netns snat-0fb68420-9e69-41bb-8a88-8ab53b0faabb qrouter-0fb68420-9e69-41bb-8a88-8ab53b0faabb ** Affects: neutron Importance: Undecided Status: New ** Tags: l3-dvr-backlog ** Tags added: l3-dvr-backlog -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1557909 Title: SNAT namespace is not getting cleared after the manual move of SNAT with dead agent Status in neutron: New Bug description: Stale snat namespace on the controller after recovery of dead l3 agent. Note: Only on Stable/LIBERTY Branch: Setup: Multiple controller (DVR_SNAT) setup. Steps: 1) Create tenant network, subnet and router. 2) Create a external network 3) Attached internal & external network to a router 4) Create VM on above tenant network. 5) Make sure VM can reach outside using CSNAT. 6) Find router hosting l3 agent and stop the l3 agent. 7) Manually move router to other controller (dvr_snat mode). SNAT namespace should be create on new controller node. 8) Start the l3 agent on the controller (the one that stopped in step6) 9) Notice that snat namespace is now available on 2 controller and it is not getting deleted from the agent which is not hosting it. Example: | cfa97c12-b975-4515-86c3-9710c9b88d76 | L3 agent | vm2-ctl2-936 | :-) | True | neutron-l3-agent | | df4ca7c5-9bae-4cfb-bc83-216612b2b378 | L3 agent | vm1-ctl1-936 | :-) | True | neutron-l3-agent | mysql> select * from csnat_l3_agent_bindings; +--------------------------------------+--------------------------------------+---------+------------------+ | router_id | l3_agent_id | host_id | csnat_gw_port_id | +--------------------------------------+--------------------------------------+---------+------------------+ | 0fb68420-9e69-41bb-8a88-8ab53b0faabb | cfa97c12-b975-4515-86c3-9710c9b88d76 | NULL | NULL | +--------------------------------------+--------------------------------------+---------+------------------+ On vm1-ctl1-936 Stale SNAT namespace on Initially hosting controller. ubuntu@vm1-ctl1-936:~/devstack$ sudo ip netns snat-0fb68420-9e69-41bb-8a88-8ab53b0faabb qrouter-0fb68420-9e69-41bb-8a88-8ab53b0faabb On vm2-ctl2-936 (2nd Controller) ubuntu@vm2-ctl2-936:~$ ip netns snat-0fb68420-9e69-41bb-8a88-8ab53b0faabb qrouter-0fb68420-9e69-41bb-8a88-8ab53b0faabb To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1557909/+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