After changing the db users pwd, re configuring data_engine and restarting the data_engine any probe that requires a connection string from data_engine in order to access the db failed to start.
In the probe logs we see a message that the logon failed for user xxxxx
When checking the data_engine connection to the db with the test button this is successful
even though the data_engine is able to connect to the db it is providing an incorrect connection string to the probes and thus they are unable to login
Release : 9.X
restarting the primary hub resolved the issue.
All probes received correct connection string and were able to start as expected