---
fixes:
  - |
    Liberal TCP connection tracking is now enabled in SNAT namespaces,
    (``sysctl net.netfilter.nf_conntrack_tcp_be_liberal=1``).

    In some cases, when a TCP connection that is NAT-ed ends up
    re-transmitting, a packet could be outside what the Linux kernel
    connection tracking considers part of the valid TCP window. When
    this happens, a TCP Reset (RST) is triggered, terminating the connection
    on the sender side, while leaving the receiver side (the Neutron
    port attached VM) hanging.

    Since a number of firewall vendors typically turn this on by default
    to avoid unnecessary resets, we now do it in the Neutron router as well.

    See bug `1804327 <https://bugs.launchpad.net/neutron/+bug/1804327>`_
    for more information.
