Beacon may stop functioning during upgrade process or if upgrade process has hung
When the Beacon is attempting to download and upgrade to a newer version the execution of tasks will pause until the process has completed.
This is by design but can cause issues where the upgrade process has hung as it leaves the Beacon in an unstable state with all activities paused.
You can identify if this is the case by looking in the BeaconEngine.log, where you may see similar to the following
2021-03-05 16:18:58,266 [llers.BeaconController|Engine] [INFO ] Beacon Controller started.
2021-03-05 16:18:58,282 [llers.BeaconController|policy] [INFO ] Updating beacon schedule with latest policy.
2021-03-05 16:18:58,282 [llers.BeaconController|policy] [ERROR] Beacon
not present in policy.
2021-03-05 16:18:58,297 [llers.BeaconController|policy] [INFO ] Updating beacon policy download interval time from latest policy, force 'True'
2021-03-05 16:18:58,297 [llers.BeaconController|policy] [INFO ] Post policy download activity skipped as FNMP Connection is disabled.
2021-03-05 16:18:58,313 [llers.PolicyController|policy] [ERROR] There is a problem on the beacon. The beacon could not determine if an upgrade is required.
This is usually caused by network issues and when they are resolved the upgrade should complete and normal operation can resume.
In cases where the upgrade still does not complete then the upgrade can be done manually which should also resolve the issue.