Hi! I would like to ask for your help on how to properly configure network routes with multiple network interface. Also, how to configure to forward the address based on which interface the traffic have originated?

OS: RHEL 8
Network management: Network Manager
Local Network:
192.168.10.0/24 (ens10) - using default gateway 192.168.10.1
192.168.20.0/24 (ens20)
192.168.30.0/24 (ens30)
External network:
172.16.50.0/24 (users network)

As example above, my server have 3 network interfaces (ens10, ens20 and ens30) and our network firewall is configured to only allow traffic from 172.16.50.0 to 192.168.20.0 or from 172.16.50.0 to 192.168.30.0

Initially, the users are not able to connect (SSH) on the server. To fix this, we created a static route using NMCLI/NMTUI. The route shows now like this and the clients are now able to connect to the server.

route -n

172.16.50.0 192.168.20.1 255.255.255.0 UG 100 0 0 ens20
172.16.50.0 192.168.30.1 255.255.255.0 UG 101 0 0 ens30

Is this the correct approach?

Our network guy also asked us about "source base routing to forward the return traffic path to the correct next hop address based on which interface the traffic have originated", is there a way to configure the network like this?