How to set up two modems(Airlink-GL6100)

That sounds like a vain hope :exclamation:

If one gets “stuck”, then why do you assume that another won’t :question:

A far better scheme would be to have some sort of “keep-alive” signal: if that stops, you know the modem is “stuck” and take the necessary action to “un-stick” it.

How are the modems controlled - external “host” or internal Open-AT application?