I'm attempting to wirelessly connect my neighbor's home network with mine. We each have our own internet services and subnets which we want to preserve, but still be able to access services between our subnets. To that end, I purchased two Ubiquiti NanoStation loco M2s and set them up in a test configuration as outlined in the diagram:
I have one M2 connected to a LAN port on my ASUS wireless router. The M2 has Wireless Mode configured as "Access Point" and Network Mode configured as "Router". The lan0 interface has 192.168.5.50/24 assigned (gateway 192.168.5.1, dns 192.168.5.1) and wlan0 is assigned 192.168.3.1/24. It has a static route, 192.168.2.0 via 192.168.3.2. From this point, I can successfully ping two existing hosts on my network, 192.168.5.10 and 192.168.5.13.
The other M2, connected to the 192.168.2.0/24 network, has Wireless Mode configured as "Station" and Network Mode also configured as "Router". The lan0 interface has 192.168.2.2 assigned (gateway 192.168.2.1, dns 192.168.2.1) and wlan0 has 192.168.3.2/24. This M2 has a static route, 192.168.5.0 via 192.168.3.1.
The ASUS router at 192.168.5.1 is handing out DHCP and has a static route, 192.168.2.0 via 192.168.5.50.
The laptop in the diagram is assigned a static address of 192.168.2.3. During testing, it was connected directly to the "far-side" M2. I could ping 192.168.2.2, 192.168.5.50, and 192.168.5.13 immediately.
This is where it starts to get strange.
When attempting to SSH from 192.168.2.3 to 192.168.5.13, the command would drag on forever, but I was eventually able to connect. I ran the command with verbose output and found that an error was occurring with GSSAPI authentication due to reverse DNS lookup failure. I added 192.168.5.1 to the list of DNS resolvers on the laptop, which fixed this issue and allowed me to connect immediately.
However, I was unable to SSH to 192.168.5.10 at all. I can ping it from the laptop, but unless I manually add a static route on the 5.10 host for 192.168.2.0 via 192.168.5.50, it won't connect. The odd thing is that the host at 192.168.5.13 does not need this static route; it connects regardless. The laptop at 192.168.2.2 doesn't have any static routes and there is no change if a static route is added.
I can ping the laptop from 192.168.5.13, however the ping output includes ICMP redirects.
How can it be that 192.168.5.13 can be accessed without a static route, but 192.168.5.10 cannot be?
Shouldn't the above access be covered by the static route entry at 192.168.5.1?
Is there any missing configuration or incorrect configuration? I was researching DHCP options 141 and 249, would that be the correct approach to fix this issue?