Some alarms do not clear or auto close from Alarm console. Why?
In one or more cases/scenarios alarm messages may not clear as expected, e.g., custom messages, invalid alarm messages, and too many other side cases to mention here.
An automatic clear message will be issued if alarm messages on breached thresholds have previously been issued and the newly-measured value is now within the threshold setting/range.
Alarm clearing across probes is currently not consistent. In general, an alarm gets cleared when the same alarm is received by the nas with a '0' severity (CLEAR), but different probes have different criteria for when they send a clear alarm. Some probes send a clear when a condition no longer exists, others do not.
If you define custom messages for instance and the variables aren't expanding due to invalid format of the variable in the message text then it will not 'match' and technically you would be getting a 0 alarm for an alarm that does not previously exist and the alarm that does exist would remain - since the nas never got an exact matching 0-sev alarm.