21.0 UNIX agent throws error: U02000313 Communication error with partner '*SERVER’' error: 'on_connection/111(connection refused)'.

Products

• CA Automic Workload Automation - Automation Engine

Issue/Introduction

Upgrading Linux agent to 21.0.3 throws the following error while the JCP is up and running:

U02000072 Connection to system ‘AUTOMICD’ initiated.
U02000379 Initiating connection to server ‘AUTOMCID’ using websocket URI: ’[IP Address]:8443/agent’.
U02000313 Communication error with partner ‘*SERVER’, error: ‘on_connection/111(connection refused)’.
U02000010 Connection to Server ‘AUTOMIC/unknown’ terminated.
U02000074 Connecting to system ‘AUTOMIC’ is not possible.
U02003073 Agent Prozess ‘AGENT,PID=136418’ shutdown has been initiated.
U02000041 Shutdown agent ‘AGENTNAME’.
U02000002 Agent ‘AGENTNAME’ version ’21.0.3+hf.1.build.23’ ended abnormally

Environment

Release : 21.x

Resolution

It is recommended that the key have a SAN that uses the IP, server name, and fully qualified domain name (FQDN).  If the certificate is one in particular, use just that one.  If it has two of these three, try each one.  The problem is that the AE is picking up one of them, but the agent is using the other.