Community discussions

MikroTik App
 
sammer75
just joined
Topic Author
Posts: 1
Joined: Thu Feb 23, 2023 9:37 am

Two networks - only syn send but no reply. Invalid response?

Thu Feb 23, 2023 10:46 am

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.

Who is online

Users browsing this forum: Ahrefs [Bot], araqiel, GoogleOther [Bot], ips, jaclaz, mkx, Seko777 and 100 guests