After several times of reboots, Legato EthLink ECM not available

Hi AE_1,
The behavior you observed could be related to the boot loop detection feature of Legato.
You can find similar log:

It is designed feature to avoid continues unexceptional reset/crash, if you want to stop this feature, please remove the bootCount file during system init.

rm /legato/bootCount

Or you should enhance your reboot mechanism, I understand you want to retry and recover from situation of no network connection… but if it is network/coverage issue it may fall into boot loop without help…
Personally, I would prefer radio on/off or restart app instead of system reboot.

Hope it helps.