Hi @alemaree, thanks for reaching out.
The relevant documentation for it is here: https://libremesh.org/docs/en_changing_network_behavior.html
Basically you will have to create a block of configuration in your /etc/config/lime-node config file, that looks like this:
config net port5 # Do not put any "." in the section name
option linux_name 'eth1.5' # Put here the actual name of the interface
list protocols 'wan' # Some of these protocols require the relative package "lime-proto-..."
list protocols 'static' # Set up a static IP (both IPv4 and IPv6 supported)
option static_ipv4 '192.168.1.2/24'
option static_gateway_ipv4 '192.168.1.1'
option static_ipv6 '2a00:1508:0a00::1234/64'
option static_gateway_ipv6 'fe80::1'
(Brought it from here: https://github.com/libremesh/lime-packages/blob/master/packages/lime-docs/files/www/docs/lime-example.txt#L210 )
where eth1.5 is the wan interface, you will need to replace this with the one listed there (don’t have a LibreRouter at hand to check which interface is the one you need to use).
You can experiment and let us know.
Also maybe others can contribute, @SAn ?