DFSMS

If you use DFSMS, submit the DISNEW (disable new allocation) command for all DFSMS managed target volumes of the session. You can complete this action through the ISMF windows before a volume migration.

Note: DFSMS is an umbrella for products such as HSM, DSS, RMM, and DFP. Except for DFP, all have control data sets. Control data sets are referred to as xCDS because the control data set can be ACDS, BCDS, OCDS, or MCDS. For more information, see Migration of control data sets.

Except for a few non-disruptive inquiries, any I/O operation to the target volume by anything other than TDMF is rejected. A message displays with IOSB completion code 4A (the I/O is prevented). The message can be IOS000I or another MVS message that indicates an error through the application or MVS system component.

The use of the DCOLLECT function against a target volume fails. The format of DFSMS error messages can be seen in the examples that follow.

Table 1. Examples of DFSMS xCDS migration error messages
IDC21807I FAILURE DURING LSPACE SERVICE (SVC 78)PROCESSING - RETURN CODE WAS 4
IDC11813I ERRORS WERE DETECTED FOR VOLSER volser. ERRORBYTE WAS X'A0'
IDC21804I FAILURE DURING VVDS/VTOC ACCESS SERVICE PROCESSING - RETURN CODE WAS X'08'
IDC11808I ERRORS WERE DETECTED FOR data.set.name ON volser ERROR BYTE WAS X'28'
IEE498I SWITCH LSPACE ERROR. RETURN CODE = 004 REASON CODE = 059 DEVICE NUMBER = dev msgtxt
Note: After the session, the DISNEW command must be disabled. Any other commands, such as the QUIENEW command, submitted against the original source volumes must also be disabled. A failure to do so can cause errors such as the ones noted previously.
Important: DFSMS operates on a volume serial number. Therefore, the status of the volumes does not change during a swap migration. The volume remains the same as before the session started. If the original source volume is renamed, it can be unrecognized by DFSMS. Thus, the original target volume serial can remain in a pool, while the new volume serial is not included in a pool.