---
issues:
  - |
    As good security practice[0], in Ubuntu Bionic the ``nf_conntrack_helper``
    is disabled.
    This causes an issue when using the ``pxe`` boot interface with the PXE
    environment that breaks some of the Ironic CI tests, since Ironic needs
    conntrack for TFTP traffic.
    It's still possible to use Ironic with PXE on Ubuntu Xenial, and it's also
    possible to use Ironic with PXE on Ubuntu Bionic using a workaround based
    on custom firewall rules as shown in [0].

    [0] https://home.regit.org/netfilter-en/secure-use-of-helpers/
