/usr/lib/firewalld/services/ Current File: //usr/lib/firewalld/services/nbd.xml

<?xml version="1.0" encoding="utf-8"?>
<service>
  <short>NBD</short>
  <description>Network Block Device (NBD) is a high-performance protocol for exporting disk images between machines.</description>
  <port protocol="tcp" port="10809"/>
</service>