Tcp Connect requests not confirmed by server - Firewall rule?

[jens888222]

I have devices which using mobile radio (4G) to communicate by Tcp with a server. My device changes to another mobile radio provider when the signal quality of the actual used mobile radio provider is bad. My device has to open again a Tcp connection (same IPs, ports).
When at a location mobile radio quality is in general bad, provider changing happens more often. In this case could it happen that my device do not get a response for Tcp connect requests.
After a manual firewall reset (States Reset) Tcp connecting works immediately.

Is there a rule in the firewall for limiting Tcp connection requests per time? Could the rule changed, one connect per minute would be good.

Thanks in advance,
Jens

[errored out]

Have you looked into Gateway monitoring?  It is not exactly the same, however, it may help with your problem.
https://docs.opnsense.org/manual/how-tos/multiwan.html?highlight=loss%20interval

Look at Loss Interval, Latency threshold and packet loss.