TNG app server is down due to ORACLE errors

Products

• Autosys Workload Automation

Issue/Introduction

App servers on ABC instance is down and couldn't connect to DB.
Error from app server log is as below: 

[05/05/2023 11:58:13]      CAUAJM_I_10655 System is running in single server mode.  Event server:  ORCL.
[05/05/2023 11:58:13]      CAUAJM_E_18407 Failed to connect to Oracle server: ORCL
[05/05/2023 11:58:13]      CAUAJM_E_18400 An error has occurred while interfacing with ORACLE.
[05/05/2023 11:58:13]      CAUAJM_E_18401 Function <Olog> invoked from <openProc> failed <163>
[05/05/2023 11:58:13]      CAUAJM_E_18402 ORA-28791: certificate verification failure
[05/05/2023 11:58:13]      CAUAJM_E_10649 Server sid was not available during connection operation.
[05/05/2023 11:59:13]      CAUAJM_E_18407 Failed to connect to Oracle server: sid
[05/05/2023 11:59:13]      CAUAJM_E_18400 An error has occurred while interfacing with ORACLE.
[05/05/2023 11:59:13]      CAUAJM_E_18401 Function <Olog> invoked from <openProc> failed <163>
[05/05/2023 11:59:13]      CAUAJM_E_18402 ORA-28791: certificate verification failure
[05/05/2023 11:59:13]      CAUAJM_E_10649 Server sid was not available during connection operation.

Bounced the app server services, services are up but still it is not working.

all commands gives error:
CAUAJM_E_10029 Communication attempt with the AutoSys Application Server has failed! [ashost:9000]
CAUAJM_E_10221 Exhausted list of available Application Server(s). Failing request.
CAUAJM_E_50033 Error initializing tx subsystem:  CAUAJM_E_10062 Failed to get initial configuration from AutoSys Application Server(s).

Environment

Release : 12.1.01

Resolution

User generated new certificates and replaced the existing ones based on the following error:

ORA-28791: certificate verification failure.

The issue was resolved with the new certificates.