Setting up for PPIT

The PPIT option can be requested on the SESSION, GROUP or REPLICATE control statement. This option is valid only if allowed by the authorization key. The PROMPT option must also be specified for all PPIT volumes, and if a PPIT volume is a member of a REPLICATE group, all other member volumes must also have PPIT specified. If the option is specified as a session or group default it will be ignored for volumes specified in MIGRATE control statements.

About this task

Options such as OVA and FASTCOPY are allowed. There are no restrictions so long as the options specified are not in conflict with each other and the customer has the relevant authorization keys.

Once the synchronization prompt has been responded to, TDMF will mark the target volume offline and ready for use with OVA if so desired. The TDMF session will not terminate once the initial PIT copy is complete. Instead a Waiting PPIT prompt is issued and TDMF will keep track of all updates to the source and target volumes until such time that the Waiting PPIT prompt is responded to. TDMF will then go into the REFRESH phase, honoring Pacing values and Active in Copy values if specified. Once TDMF has determined that it can synchronize the volumes, the synchronization prompt will be issued again. There is no limit to the number of synch-points that may be taken within a single session.

Important: If the PPIT migration source volumes exploit the Parallel Access Volume (PAV) feature, the PAV option should be specified on the SESSION, GROUP or REPLICATE control statement. Failure to do this will result in the PAV feature being disabled (no bound alias devices) for the duration of the perpetual migration, with a probable impact on performance for the applications using the volumes. The trade off here is that the PAV option causes TDMF to allocate 16 KB of fixed HVCOMMON storage for every bound alias device on every participating system.