Step 2. freeze updates to the primary volume

Issue the CGROUP command with the FREEZE option specified (one command per storage control or LSS) to freeze I/O updates to the primary volume. Freezing your secondary volume ensures that it is consistent with the primary volume, but any updates made to the primary volume after the freeze are not reflected on the secondary volume. To freeze updates to the primary volume, issue the following command:
CGROUP DEVN(X'0F41') PRIM(X'A763' FCA76 X'6B' X'03') SEC(X'A762' FCA76 X'1E' X'02') FREEZE
Note: The CGROUP command enables the extended long-busy condition when the state of the volume pair changes to the SUSPENDED state. The application programs making updates to primary storage controls receive a long-busy condition.
Results: When you freeze I/O updates to the affected primary volume of an LSS pair, the following conditions occur:

Continue with Step 3. resume operations after a freeze.

For additional information about fuzzy volume copies, refer to Establishing PPRC volume pairs.