Chapter 16. Moving recoverable data sets that have retained locks

There may be times when you need to re-define a VSAM data set by creating a new data set and moving the data from the old data set to the new data set.

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For example, you might need to do this to make a data set larger. In this case, note that special action is needed in the case of data sets that are accessed in RLS mode by CICS regions.

Recoverable data sets may have retained locks associated with them. For data sets accessed in RLS mode, SMSVSAM associates locks with the physical location of the data set on disk. If you move the data set from one disk location to another, ensure that any retained locks are associated with the new data set location after it is moved. DFSMS access method services provide some SHCDS subcommands that enable you to preserve these locks when moving a data set.

Procedure for moving a data set with retained locks

This topic outlines some procedures to follow when moving a data set from one location on DASD to another.

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There are two basic methods that you can use to move a VSAM data set:

1.Use the REPRO function of the access method services utility, then delete the original data set.

2.Use the EXPORT and IMPORT functions of access method services.

With either of these methods, you need to take extra steps to preserve any retained locks for data sets accessed in RLS mode.

Using the REPRO method

If the recoverable data set you want to move has not been used in RLS mode, you can use access method services commands to perform a number of actions on it.

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These actions include:

1.Create a new data set

2.Copy (REPRO) the data from the old data set to the new

3.Delete the old data set

4.Rename the new data set back to the old

In the case of a non-RLS mode data set, retained locks are not a problem and no other special action is needed.

© Copyright IBM Corp. 1982, 2010

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IBM SC34-7012-01 manual Moving recoverable data sets that have retained locks, Using the Repro method