DEFRAG with a Primary and Shadow MUF
Article ID: 107007
Updated On:
Products
Issue/Introduction
Can DEFRAG be run with a Primary and Shadow MUF?
Datacom Core - 15.1 section on “DEFRAG (Defragment Index)”
says “Cannot be run in a MUFplex environment if two or more MUFs are enabled“
Is this restriction true for a Primary and Shadow setup?
Environment
Resolution
There is no concern running a DEFRAG to a primary MUF that has a Shadow MUF in waiting
Given startup option: MUFPLEX plexname,*,,250,S
The MUFPLEX mode 'S' confirms that no structure CF coupling facility is being used.
As per documentation on MUFPLEX and mode S:
"To run in a Shadow MUF environment, specify an S as the mode for the MUFPLEX MUF startup option. For each physical MUF involved in the Shadow MUF environment, you should specify S for the MUFplex mode. A MUFPLEX mode of S is like a MUFPLEX mode of B in that no pipeline writes are done to the Coupling Facility. Implementation of mode S has only a small effect on how MUFPLEX modes A and B execute. For more information about running in a Shadow MUF environment, see Shadow MUF Environment.
The concern would be if a true multi-MUF environment was set up and using a CF structure with a different mode.
DBUTLTY DEFRAG can be run from any lpar that has access to the active MUF via XCF.
Example:
Primary running on LparA and Shadow waiting on LparB.
Batch DBUTLTY with...
/*JOBPARM SYSAFF=*
... and ...
//SYSIN DD *
DEFRAG DBID=dbid
/*
As long as the MUF is active (ENABLED) on either lpar, the DBUTLTY job will run via XCF from the submitted lpar (/*JOBPARM SYSAFF=*).
Additional Information
Refer to Datacom Core - 15.1
Section on DEFRAG (Defragment Index)
Section on MUF startup option MUFPLEX
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