gateway problems

[unixpgmr]

I know I am just missing something but I can't seem to get a gateway set up properly. I have 5 interfaces:
WAN
LAN: 10.20.0.0/24
OPT1
OPT2
OPT3:173.20.2.0/24

I want to be able to get from my LAN to OPT3. I can't seem to figure out the gateway to get this to work.  Any hints would be beneficial.

Thank you in advance for your time.

[marjohn56]

Create firewall rule on the OPT3 net, you need to allow source from from LAN net. If you want to talk from OPT3 to LAN you need to create a similar rule for the LAN.