Linksys MX4200

Installing and Using OpenWrt
1

I try to install OpenWrt on a Linksys MX4200.

Installing the bare OpenWrt 25.12.4 worked.

However, after configuring the firewall port forward settings, the router reboots continuously after Luci login or ssh login.

I did several rounds of reset but there is no way to get a stable configuration. As soon as port forwarding rules are added, the same behaviour reappears.

Session expired

A new login is required since the authentication session expired.

Did anyone experience this behaviour?
Does anyone have an explanation?
How can I remedy this behaviour?

2

What is the port forward you added? Are you sure the device is actually rebooting (please indicate specifically what makes you believe it is actually rebooting vs other behaviors)?

Did you add the forward via LuCI or cli? Pleas show us what you’ve added.