From Application Server Logs, Error messages indicate the there is an issue with network communication.
Database indicates cannot be reachable.
Release : 11.3.6*
Component : CA Workload Automation AE (AutoSys)
WCC Collector Fails/retries to fetch job details when such issues occur.
should work with network admins team to find out cause for disconnection.
Please troubleshoot and follow up below list to make sure you address network issue
Database Drivers Connectivity
Port Communication Blockages/changes
FQDN/DNS name resolution or IP address changes