Perplexing PPPoE Management problem

Hello,
First post here.
I’m having an issue with accessing a modem and other equipment across a WAN port. Funny thing is that I used to be able to and now can’t.
Balance 20, Fimware 8.1.0.

My main untagged LAN is 192.168.0…, and the modem and other stuff is on 172.168.0…

I set the Management IP address for that PPoE WAN to the unused 172.168.0.1 address and I can’t connect or ping over the switch anything on that subnet.

No idea, and hoping someone here can help.

Thanks

Found the problem.

Apparently, you can only have one device on the back side of the WAN port using PPPoE with a Management IP address.

With one device on the subnet, I can connect to it, two or more and I can not connect to any of them.

My setup is DSL Modem → Tsunami Radio → Tsunami Radio → Peplink Balance Wan 1

If I set the management IP to say 10.10.0.1/24 and the modem and radios to .4/24, .3/24, and .2/24 respectively I can not connect to any of them.

If I change the management IP to say 10.1.0.1 and change either of the radios or modem to the 10.1.0. subnet, I can connect fine to it.

Is this a bug or has the PPPoe management feature been designed this way?

Either way, it a pain because the modem and one of the radios is .5 miles away as the crow flies, and 2 miles if I drive.

Couldn’t get an enforced rule or a static route to work either.