roe1974 write
What with this ?
If your ISP not block a detection communication then this will work.
How work? Read manual: Detect Internet - RouterOS - MikroTik Documentation
You can always enable that feature and watch status of contrack
while (1=1) do={delay 1s ; ip firewall connection print where dst-address~":30000" }
You can write your own detection... like I do when CHR works as my own LoadBalancer unit, you have many options.
For LTE connections remember about:
Enable logs by: /system logging add topics=lte
Simple watchdog: Sxt LTE 4g+ Cat6>
Advance watchdog: tx rx fp rx dropped pppoe account
Watch LTE parameters: R11e-LTE6 2CA not staying connected - #22 by Ferrograph
Documentation: RouterOS - RouterOS - MikroTik Documentation