Fix proposed to branch: master Review: https://review.opendev.org/c/openstack/neutron/+/871659
** Changed in: neutron Status: New => In Progress -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1834213 Title: After kernel upgrade, nf_conntrack_ipv4 module unloaded, no IP traffic to instances Status in OpenStack Neutron Open vSwitch Charm: Fix Released Status in neutron: In Progress Status in linux package in Ubuntu: Confirmed Bug description: With an environment running Xenial-Queens, and having just upgraded the linux-image-generic kernel for MDS patching, a few of our hypervisor hosts that were rebooted (3 out of 100) ended up dropping IP (tcp/udp) ingress traffic. It turns out that nf_conntrack module was loaded, but nf_conntrack_ipv4 was not loading, and the traffic was being dropped by this rule: table=72, n_packets=214989, priority=50,ct_state=+inv+trk actions=resubmit(,93) The ct_state "inv" means invalid conntrack state, which the manpage describes as: The state is invalid, meaning that the connection tracker couldn’t identify the connection. This flag is a catch- all for problems in the connection or the connection tracker, such as: • L3/L4 protocol handler is not loaded/unavailable. With the Linux kernel datapath, this may mean that the nf_conntrack_ipv4 or nf_conntrack_ipv6 modules are not loaded. • L3/L4 protocol handler determines that the packet is malformed. • Packets are unexpected length for protocol. It appears that there may be an issue when patching the OS of a hypervisor not running instances may fail to update initrd to load nf_conntrack_ipv4 (and/or _ipv6). I couldn't find anywhere in the charm code that this would be loaded unless the charm's "harden" option is used on nova-compute charm (see charmhelpers contrib/host templates). It is unset in our environment, so we are not using any special module probing. Did nf_conntrack_ipv4 get split out from nf_conntrack in recent kernel upgrades or is it possible that the charm should define a modprobe file if we have the OVS firewall driver configured? To manage notifications about this bug go to: https://bugs.launchpad.net/charm-neutron-openvswitch/+bug/1834213/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp