NFS and Fedora

I’m running Fedora 25 on a desktop PC.

I have Libreelec with kodi 17 on my HTPC.

Desktop PC has NFS shares yet when the firewall is on the HTPC can’t access. I’ve turned off the firewall and everything works but I would prefer to have a firewall on.

I’ve tried opening up the NFS ports on the firewall on the Fedora machine but still no joy.

What ports and for what protocols do I need to open?

Cheers.