After upgrading the snmpcollector probe to 4.03 some devices have stopped collecting metrics
Specifically the Reachability metric for the device which showed as 100 i.e. available following the upgrade then just dropped to 0 at some point i.e. unreachable.
Rediscovering the devices and validating credentials did not help.
Forced component rediscover which passed but on some devices this error is seen:
"Discovery Failed - Credentials Invalid or device is unreachable. Unable to communicate with device using given credentials"
Release : 9.2.0
Component : UIM - SNMPCOLLECTOR
snmpcollector-4.0.3-HF3 can be requested through a Support Case.
Also see the following article for other causes for Reachability being 0 for an accessible device: