Windows Agent 12.2 cannot connect to 21.0 CP during ZDU

Products

• CA Automic Workload Automation - Automation Engine

Issue/Introduction

A 21.2 Windows agent that is license class 'S' is unable to connect to the version 21.0 CP during Zero Downtime Upgrade (ZDU). 

According to the Windows Agent log on the AE server, it cannot find a CP port.  The license class has always been set to 'S'.  The logs states:

Agent has been started with license class 'S'.  Ignoring configuration parameter cp=.  The connection '127.0.0.1:2217' is used instead.
Agent has been started with license class 'S'.  Ignoring configuration parameter cp=.  The connection '127.0.0.1:2218' is used instead.
Agent has been started with license class 'S'.  Ignoring configuration parameter cp=.  The connection '127.0.0.1:2223' is used instead.
Agent has been started with license class 'S'.  Ignoring configuration parameter cp=.  The connection '127.0.0.1:2222' is used instead.

That is the port used for CP.  So, it should connect.  However, the log shows 

2000011 Connection to Server '127.0.0.1(SERVERNAME):2218' initiated.
20220517/142017.913 - U02000004 Connection to Server 'UC4#CP004' successfully created.
20220517/142017.913 - U02000354 CP Server 'UC4#CP004' reports ranking '9999'.
20220517/142017.913 - U02000076 Connection to CP Server 'UC4#CP004' closed.
20220517/142017.913 - U02000011 Connection to Server '127.0.0.1(SERVERNAME):2217' initiated.
20220517/142017.945 - U02000004 Connection to Server 'UC4#CP001' successfully created.
20220517/142017.945 - U02000354 CP Server 'UC4#CP001' reports ranking '9999'.
20220517/142017.945 - U02000076 Connection to CP Server 'UC4#CP001' closed.
20220517/142017.945 - U02000011 Connection to Server '127.0.0.1(SERVERNAME):2223' initiated.
20220517/142018.968 - U02000012 Connection to Server '127.0.0.1:2223' denied.
20220517/142018.968 -                    Connect-Error: 10061 (No connection could be made because the target machine actively refused it.)
20220517/142018.968 - U02000011 Connection to Server '127.0.0.1(SERVERNAME):2222' initiated.
20220517/142019.984 - U02000012 Connection to Server '127.0.0.1:2222' denied.
20220517/142019.984 -                    Connect-Error: 10061 (No connection could be made because the target machine actively refused it.)
20220517/142019.984 - U02000074 Connecting to system 'UC4' is not possible.

Environment

Release : 21.0.1

Component :

Resolution

After finalizing the ZDU, the agent connected again to the system.