logging

PagerDuty(https://www.pagerduty.com/) is widely used for on-call globally. We are welcome the contributions to support it as alarm notification channel.

Describe the bug
If Loki Recording Rules are used with remote-write to a Prometheus instance, which does not have remote-write enabled (--enable-feature=remote-write-receiver), then Loki will fail to remote-write to Prometheus and fail silently.
I have tried this with log-level info, which should include any such e

Logstash information:

Please include the following information:

1. Logstash version: 7.16.3 (with unverified reports of similar behaviour on 7.15)

   Looking through our case history there were examples of this issue happening after upgrading to 7.15 and higher. The odd behavior is this appears to be intermittent in most cases, and the cases closed out without resolution. Confirmed

This happens occasionally when shutting down the server:

Exception in thread "http-worker-15" java.lang.NullPointerException: null value in entry: exception=null
        at com.google.common.collect.CollectPreconditions.checkEntryNotNull(CollectPreconditions.java:32)
        at com.google.common.collect.ImmutableMap.entryOf(ImmutableMap.java:176)
        at com.google.common.collect.I

The generic Windows audit log config lacks many event ids, e.g.

• registry events
• driver load service addition events, System/7045 and Security/4697
• likely others