In the processes probe, I have set the probe to alert when a process goes down, and have also set expected instances = 1.
When I get more than one instance of the monitored process, I get an alarm as expected, but when I kill the 2nd instance, I get an unexpected "process is down" alarm.
The process is not down, the "second" instance of the process is down, but this should not generate an alert because this is an undesired process that should not be running in the first place.
How can we avoid getting this erroneous alarm?
Release : 20.4
the way to avoid this is NOT to alarm on both "when down" and "expected instances".
if you set an expected number of instances, you will also still get an alarm if the (single) process goes down, because the number of instances will be 0 and the expected will be 1.
Likewise, if you had 2 copies of the process, you'd get the "expected 1, found 2" alarm. If the 2nd, "extra" one went down, this alarm clears and you wouldn't get an alarm for the 2nd process going down (unless both went down and you'd get the "expected 1, found 0" alarm.