After a failover, when the secondary DA came online, things appeared to be working at first but on further investigation, the following was noticed:
a. Sync failed
b. DCs could not connect
c. ../rest/devices showed ONLY the Data Aggregator
d. DA karaf.log showed messages regarding issues reading iRep
WARN | esponseHandler-1 | 2021-02-08 10:43:09,858 | AbstractPollResponse | re.common.AbstractPollResponse$1 658 | m.ca.im.data-mgmt.common | | Attribute id 7731 does not exist in poll group 5315; DC out of sync?
ERROR | plyEnvSensorInfo | 2021-02-08 10:43:09,858 | ExceptionLog | .ca.im.core.util.ExceptionLogger 104 | m.ca.im.common.core.util | | An existing application exception RECURRED (Key=246fb071054ab6b4476bfd95439d9c87744d096f), Recurrence count=9 : Look up requested for DCM ID hostname:dbd24d69-ea0f-4466-bede-7ff82c3e7b82 but iRep did not return any items. : For input string: "hostname:dbd24d69-ea0f-4466-bede-7ff82c3e7b82"
The Data Aggregator user was set differently for the Secondary Data Aggregator
Release : 20.2
Component : CA Performance Center
The /opt/IMDataAggregator/apache-karaf-2.4.3/etc/dbconnection.cfg file should be the same between both Data Aggregators. When the Secondary Data Aggregator is not running, copying the primary (working) dbconnection.cfg over the top of the secondary (not working) dbconnection.cfg should allow the Secondary Data Aggregator to start properly.