Reviewed: https://review.openstack.org/503890 Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=fd1403fd9a971cf3cbd863fa33ca68eb019fbdc1 Submitter: Jenkins Branch: master
commit fd1403fd9a971cf3cbd863fa33ca68eb019fbdc1 Author: Sławek Kapłoński <[email protected]> Date: Thu Sep 14 02:11:50 2017 +0000 Fix for race condition during netns creation In some cases if ip_lib.IPWrapper.ensure_namespace() method is called more than once for same namespace in very short period of time it could raise error that "File already exists" for second call of this method. It happens often e.g. in fullstack tests. Reason of such problem is in Netlink protocol which is used by iproute2 to communicate with kernel. This protocol, according to http://man7.org/linux/man-pages/man7/netlink.7.html is not reliable so it is not guaranteed when the message will be delivered to kernel and when action will be really executed. Because of that if on quite loaded host ensure_namespace() method would be executed twice it can lead to error described above. This patch is changing way how ensure_namespace() method works to avoid raising ProcessExecutionError exception with this error message. Closes-Bug: #1717582 Change-Id: I1898426789c85ce1faa97665bfd47f1fa38ef727 ** Changed in: neutron Status: In Progress => Fix Released -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to neutron. https://bugs.launchpad.net/bugs/1717582 Title: fullstack job failing to create namespace because it's already exists Status in neutron: Fix Released Bug description: In fullstack tests there is many times error with creating e.g. "host-xxxx" namespace. Error message tells that such namespace already exists and test is failing because of that. It looks that this is kind of race condition when ip.netns.exists() method return false but few miliseconds later namespace already exists and ip.netns.add() method fails. It is in method ensure_namespace() in https://github.com/openstack/neutron/blob/master/neutron/agent/linux/ip_lib.py#L204 To manage notifications about this bug go to: https://bugs.launchpad.net/neutron/+bug/1717582/+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
