MFE ConGroup: Enhancement: Dynamic Configuration Change Recognition

When doing dynamic adds or removals, in a multi session ConGroup (CG), the value changes are only temporarily. In order to make them permanent, the user must do a CG refresh when MSC is disabled. In this situation, the customer was running GDDR and one of the managed LPARs was IPLed and it no longer had the dynamic changes. Thus, the error message CGRP653E was displayed.

Once the CG owner issued the refresh to all LPARs and completed the refresh, then the IPLed LPAR could bring CG back up successfully. The customer wants to prevent similar scenarios from occurring by being notified of any dynamic configuration changes in the system that have not been committed. They want the systems to be smart enough to alert them when there is a difference between committed and uncommitted configuration changes.

The customer had over a period of three months done multiple dynamic adds and deletes to their ConGroup defined devices. Then they IPLed one of their ConGroup managed LPARS only to receive the CGRP653E error message when starting up that ConGroup started task. 

CGRP653E Configuration File Mismatch: EMCL ANCGP84L - Shutting Down

Per the documentation:  
Dynamic addition and removal modify the running ConGroup configuration. This is true for one or more connected ConGroup address spaces. Dynamically added or deleted devices are not reflected in the new configuration. If a restart of ConGroup (or a refresh) occurs, the dynamic changes are lost. In other words, dynamic add or delete is not persistent.

Once a dynamic ADD or DELETE is done, ConGroup no longer permits a new started task to join the network of existing connected ones. This is because a new ConGroup could possibly be using a configuration file that does not match the running configuration. If a new ConGroup address space is started, it is forced (by the other ConGroups) to shut down immediately. The interloping ConGroup issues the message CGRP653E before it comes down.

The enhancement request is to allow a customer to be notified of the situation. So that they can plan accordingly instead of being surprised at an inopportune time such as during an IPL of one of the ConGroup group members. 

• For Mainframe Enablers 10.0.0, PTF SCA0005 has been developed to correct the issue. It is available to download from Dell Technologies Online Support.
• For Mainframe Enablers 8.5, PTF SC85020 has been developed to correct the issue. It is available to download from Dell Technologies Online Support.

The enhancement update provides the following messages changes: 

When any successful dynamic ADD or DELETE is performed, the following message is appended to the usual message's attendant to the dynamic operation:

CGRP626W Warning: REFRESH required before new CG nodes can be added to the network

This provides an easy-to-understand warning that a refresh may be required.

The output of the 'DISPLAY ENV' command has been augmented to include the following depending upon the condition of the configuration: 

CONFIGURATION STATE:
PHYSICALLY MODIFIED. REFRESH MAY MODIFY RUNNING CONFIG.
DYNAMICALLY MODIFIED. REFRESH REQUIRED BEFORE ADDING NEW NODES.

Or

Finally, if a new ConGroup node is started and it is not allowed to join the network, one of the following messages is issued. 

CGRP653E now has "File Difference" or Dyn Change" as embedded reason strings:
CGRP653E Configuration Mismatch: N247 LJCGP10 File Difference - Shutting Down

Or

CGRP653E Configuration Mismatch: N247 LJCGP10 Dyn Change - Shutting Down