RPi3 PXE boot - how to control which NFS port is used

    Hi all,

    After spending a few afternoons puzzling together all the tidbits of configuration required, I've got my RPi3 successfully PXE-booting LibreElec 9.0.2 off of my Ubuntu server.

    There is however one final challenge; LibreElec uses random (high) port numbers (seems to vary between 30000 and 50000) to mount my System and Storage NFS shares. My firewall does not agree with this. I had initially set Shorewall to allow ports 111 and 2049 for NFS. Only after disabling Shorewall could the Pi mount the NFS shares and boot to Kodi.

    How do other PXE users handle this?

    Is there a way to control the port used by LibreElec to NFS-mount?

    Or a clever firewall rule to accommodate this in a reasonably secure way?

    Running without firewall, even if it's just on my local LAN, does not feel quite right.

    Thanks for any help!