Two subnets again

[KatzSmile]

Hello.

There is a connectivity problem between two subnets.

LAN1 192.168.0.0/22 ​​where the server with OPNsense 192.168.1.21 is specified as the gateway

OPNsense is connected to three networks:
to network 192.168.0.0/22 ​​via interface 192.168.1.21
to network 192.168.5.0/24 via interface 192.168.5.21
to the Internet via WAN1 interface

LAN2 192.168.8.0/22 ​​with Router 192.168.8.1 specified as gateway

Router is connected to three networks:
to network 192.168.8.0/22 ​​via interface 192.168.8.1
to network 192.168.5.0/24 via interface 192.168.5.1
to the Internet via WAN2 interface

Router and OPNsense are both connected to the network 192.168.5.0/24 and through the interfaces 192.168.5.1 and 192.168.5.21 respectively, and can see and ping each other without any problems.

OPNsense has a static route to the 192.168.8.0/22 ​​network through the 192.168.5.1 Router and can see and ping computers in the 192.168.8.0/22 ​​network without problems.

There is no access to setup or configuration of the 192.168.5.1 Router or any computers in the 192.168.8.0/22 ​​network.

How can I make computers from the 192.168.0.0/22 ​​network see and ping computers in the 192.168.8.0/22 ​​network?

UPD: I forgot to mention that if you specify the subnet 192.168.5.0/24 on ANY device with the gateway 192.168.5.1, then this device will able to see and ping the subnet 192.168.8.0/22 without problems

Please help.

I have attached a network diagram.

[lilsense]

you are missing the 2nd half of your problem. you need a static route on the other router for the LAN1 network.

[KatzSmile]

you are missing the 2nd half of your problem. you need a static route on the other router for the LAN1 network.

yeah. cant do that. Router isnt accessible for any changes.

[lilsense]

yeah, you are not gonna talk... LOL

your traffic gets there, but no route to get back.

[Patrick M. Hausen]

yeah. cant do that. Router isnt accessible for any changes.

Then you need to NAT. Without a route in the upstream router you simply cannot use any additional subnets. Matter of fact.

[KatzSmile]

UPD: I forgot to mention that if you specify the subnet 192.168.5.0/24 on ANY device with the gateway 192.168.5.1, then this device will able to see and ping the subnet 192.168.8.0/22 without problems