IBM SG24-5360-00 manual Ramac Virtual Array, Peer-to Peer Remote VSE/ESA

access method (SAM) files, however, can be relocated to a different, single extent disk location on the target device. In this case, the tcyl operand must be supplied, but the device must not be a VM partial pack minidisk. The proper label information (single FORMAT-1 label) will be created and added to the target VTOC. Processing multivolume files is the responsibility of the operator, such that the SNAP command should be repeated for all the source volumes containing file extents. The number of extents to be copied is limited by the limits existing for the source device. Copying will be performed only if the appropriate extent boundaries on the target device are available or have already expired. Otherwise an error message will be issued. Use the DDSR command to delete the overlaid file and release the space.

target The device ID (cuu) or the VOL1 label of the target device to which the user wants the data to be copied. You must set the target device DOWN (DVCDN command) before initiating the SNAP function, unless the source and target devices are the same device. If the target device is identified by its VOLID, it must be either the only volume with that VOLID or the only volume with that VOLID that is DOWN (DVCDN). Otherwise an error message is issued. As many extents as allocated on the source device will be used for file copying to the target device (DSN=) . Otherwise as many cylinders as specified for the source device, or the entire source volume will be copied to the target device. Relocation of data records will be assumed if the specified cylinder range does not match the cylinder range that was given for the source device. If the cylinder range does not match the cylinder range of the source device and the target device is a VM partial-pack minidisk, the command will be rejected because VM uses virtual cylinder values for partial-pack minidisks, and the cylinder ranges must match for VM partial-pack minidisks. The source and the target devices must be of the same type and must be in the same RVA subsystem.

tcyl The decimal specification of where copying is to start on the target device. Cylinder is the smallest entity that can be specified for any SNAP command function. The target cyl specification (tcyl) added to the specified or calculated ncyl-1 value for the source device is the resulting target end cylinder address and must not exceed 32767 or the device′s primary number of cylinders.

V O L 1 = Specifies the VOL1 label that the target device is to receive after the source volume has been copied. This operand is required if unique VOLIDs are to be maintained. Otherwise the source and the target devices would have the same VOL1 label after the copy function has completed. The VOL1 label specification for a target device is accepted only when both the cyl and the DSN= specification have been omitted, that is, for full volume snaps only.

44 RAMAC Virtual Array, Peer-to Peer Remote VSE/ESA