[FEATURE] static mountd port

[sylvainfaivre]

Is your feature request related to a problem?

Using default settings, the NFS mountd service listens on a random port.
An option to set up a fixed port would be nice, in order to be able to open that port on the firewall settings.

Describe the solution you'd like

On Debian distro, this setting can be used in /etc/default/nfs-kernel-server (only relevant lines copied below) :

# Options for rpc.mountd.
# If you have a port-based firewall, you might want to set up
# a fixed port here using the --port option. For more information, 
# see rpc.mountd(8) or http://wiki.debian.org/SecuringNFS
# To disable NFSv4 on the server, specify '--no-nfs-version 4' here
RPCMOUNTDOPTS="--manage-gids"

It would be nice to have an option to add the --port xxxxx setting to this line.

Describe alternatives you've considered

Additional context

[myii]

Useful reference: https://wiki.debian.org/SecuringNFS.

[sylvainfaivre]

Yes, that link is referenced in the comments I quoted ;-)

My point is, we know how to setup that setting, but it would be nice if the formula allowed to do it.

[myii]

Yes, that link is referenced in the comments I quoted ;-)

Ah, but you didn't turn it into a hyperlink for following easily!

My point is, we know how to setup that setting, but it would be nice if the formula allowed to do it.

Sure, would you like to provide a PR for this?