[
{
  type: upgrade
  maximum_version: "4.6.4"
  message: <<EOM
Upgrading from before 4.6.4, old ser2net configuration is not supported anymore.
You must convert the existing configuration into the new YAML format.
See ser2net.yaml.sample and ser2net.yaml manpage for more details.

Additional resources can be found on the following wiki page:
https://wiki.freebsd.org/RodrigoOsorio/HowTo/Ser2Net
EOM
}
]