[Question] <How to get notifications when a collector deployed in an asymmetric network is offline>

### Question

A collector deployed in a one-way network node may go offline due to host or network issues.
At this point, all monitoring tasks bound to this collector cannot be updated, which may lead to subsequent internal monitoring node failures being missed.

On this basis, how can you configure an alert for collector offline?

At least this way, the hertzbeat will be notified of collector offline and respond in time.

The issue does not identify files, tests, or an implementation entry point. First determine whether collector-offline detection and alerting already have a relevant configuration path; define the expected alert trigger and recovery behavior before locating the affected collector and notification components.

Written by the indexing model from the issue text.