Different Methods of Fallback to Datacom/AD 15.0 from 15.1

Products

• Datacom
• Datacom/AD

Issue/Introduction

How do we back out of CA Datacom/AD 15.1 to 15.0?  

We have a QA Datacom MUF with no Shadow and for our Production Datacom, we have a primary/shadow MUF configuration.

Environment

z/OS

Resolution

(I) Having no shadow, you would perform a switch to the old 15.0 libraries (CUSLIB and LOADLIB) from 15.1

(II) For shadow MUF, there are two scenarios.

Scenario A:

1. MUF-A (Primary) is running at 15.0. you install the new 15.1 load library into the MUF-B (Shadow) JCL and submit.

2. At the desired time, you issue a EOJ MUF-A (Primary 15.0) to shut it down and MUF-B (Shadow 15.1) becomes Primary.

3. Testing and validation are done in MUF-B (Primary 15.1). 

4. It will be your decision on whether you want to start MUF-A (Shadow MUF) as 15.0  (for potential fallback), or as 15.1 (for longer-term operation). Modify MUF-A JCL if needed for 15.1, and then start MUF-A as Shadow.

5. If you are running MUF-B (Primary 15.1) and MUF-A (Shadow 15.0) and decide you need to fallback to 15.0, then you would EOJ MUF-B (Primary 15.1), and MUF-A (Shadow 15.0) takes over as Primary.

Scenario B:

1. If you have both MUF-B (Primary 15.1) and MUF-A (Shadow 15.1) running, and later determine that you need to fallback, then EOJ MUF-A, replace the STEPLIB with the 15.0 load library, then start MUF-A as shadow. When ready, you will EOJ MUF-B (Primary 15.1), and MUF-A (Shadow 15.0) takes over as the Primary MUF.

Additional Information

Check our CA Datacom/DB documentation 'Use Case Videos' on how to setup a Shadow MUF

Check the CA Datacom/AD documentation for Active Upgrade

Check Knowledge Article 204117: CA DATACOM/AD active MUF upgrade from 15.0 to 15.1

Check Knowledge Article 199604: How to Fallback to AD 14.0 and when to run AXACTDDR