Use the CESTPAIR command to specify PPRC primary and secondary
volumes. In order for this command to complete successfully, a PPRC
link must be active between the primary logical subsystem and the
secondary logical subsystem.
When establishing a pair of System z® devices, the primary and secondary volumes must have the same
number of tracks on each cylinder and the same number of bytes on
each track. The secondary device must have the same number or a greater
number of cylinders as compared to the primary device. For open devices,
the secondary volume must have capacity equal to or greater than the
primary volume.
Note: - Peer-to-peer remote copy allows you to copy data from a smaller
primary device to a larger secondary device . (For System z volumes, the track size and number
of tracks per cylinder must be the same.) The additional space on
the secondary volume may not be immediately usable. End the PPRC volume
pair and run ICKDSF Release 17 or above against the secondary volume
to rebuild the VTOC and make the additional space usable.
- Because multivolume data sets span multiple volumes, they require
special handling. To ensure that the data set is recoverable, copy
all volumes of multivolume and striped data sets.
- For more information and examples, see Adding a PPRC volume pair.