Hi,
I have following scenario:
-LAN A|10.96.147.64/27|----eth2|10.96.147.65| RouterA |10.96.149.240|eth1--------LAN B|10.96.148.0/23|-----10.96.148.1|RouterB
If Clients from LAN A want to reach services on LAN B, I can see on RouterA syn packets sent, but no reply. On RouterB is a route to10.96.147.64/27 which points to gateway 10.96.149.240. Adding a static route on clients like the above one, makes the connection work. There are no firewall rules on RouterA and no NAT.
I think the connection way, without the static route on a Client B, is, that the client from LAN A initiates the connection to a client in LAN B. The client in LAN B sends his reply to Router B because he don't know the way to the LAN A. Router B routes to Router A, but Router A rejects the reply as invalid because he expects the reply from clients address from LAN B.
Am I right with my assumptions and what can I do to resolve this problem? Sorry if this is a beginner question or if I forget something.
Many thanks.