Adding a volume with the FULLCOPY or QUICKCOPY option

Unless you specify NOCOPY, XRC makes an initial copy of the primary volume. Use Table 1 to determine which copy option to choose.

Table 1. Copy option determination
If you use . . .	Then . . .	Notes . . .
The default FULLCOPY option	XRC copies all tracks on the primary volume to the secondary volume. As each track is copied, the primary subsystem adds the track to the storage control session and starts monitoring that track for updates to ensure they are captured during the copy process. The SDM does this by reading a number of tracks in a single channel command word (CCW) chain and, in the same chain, adding those tracks to the storage control session. If you are using the FULLCOPY option for tracks that have never been written or that contain an end-of-track indicator, data will not be transmitted (it is an empty track). For tracks that have been written to or are in the volume table of contents (VTOC), data will be transmitted.	You may change the default by using the XSET COPY option. See XSET command syntax.
The QUICKCOPY option	XRC copies only allocated tracks on the primary volume to the secondary volume during this initialization of the secondary volume. Initialization of the secondary volume is performed while copying primary volume updates to the secondary volume.	During this processing, XRC does not copy the volume serial number from the primary volume to the secondary volume. Therefore, during normal copy operations, a display of the secondary volume serial number shows its original serial number. During XRECOVER processing, XRC sets the secondary volume serial number equal to the serial number of the primary volume; this is not performed for XADVANCE processing.

Note:

The choice to use the FULLCOPY or QUICKCOPY options for the synchronization process depends on a number of factors. If you are using channel-extension technology, you should use the FULLCOPY option as there is risk that a reserve could be left outstanding on the primary device if the network fails during the copying process.
XRC ensures that it has successfully copied all tracks (with FULLCOPY) or all allocated tracks (with QUICKCOPY) on the primary volume, and all updates that are made to the volume during initialization, to the secondary volume. As a result, when volume initialization is complete, the secondary volume is in a known, consistent state.
If you have a restricted amount of bandwidth between the primary and secondary devices, then specifying the QUICKCOPY option may be extremely beneficial. Performing a large number of full synchronizations of primary and secondary devices increases the benefit of using the QUICKCOPY option.
As part of the resynchronization function, XRC automatically copies all changed and any not previously copied tracks whenever suspended volume pairs are added again to a session. For this resynchronization function, XRC ignores any copy option specified.