Recovering backup versions from a damaged migration level 1 volume

Use the following steps to recover backup versions from a damaged migration level 1 volume.

Issue the following Access Method Services command to print a list of MCM records. Use this list to determine if any of the backup versions on a damaged or restored ML1 volume are still valid.
```
PRINT IDS(bcds-dsname) FROMKEY(X'26') -
TOKEY(X'26') OUTFILE(ddname)
```
For bcds-dsname, substitute the fully qualified data set name of the DFSMShsm backup control data set. For ddname, substitute the DDname of a preallocated data set that contains the output from the PRINT command.
Examine each MCM record that was printed to see if it represents a backup version that resides on the migration volume being recovered. To do this, look at offset 152 (X'98') in the record for the ML1 volume serial number. For all MCM records that have the volume serial number of the volume being recovered, you should perform the following. For dsname in the following commands, use the original data set name found at offset 64 (X'40') of the MCM record.
1. Use the following DFSMShsm command to find out the version number of the backup version indicated as being on the volume being recovered:
```
LIST DATASETNAME(dsname) BACKUPCONTROLDATASET
```
2. Using the version number found in the previous step, issue the following DFSMShsm command to delete that backup version:
```
BDELETE dsname VERSIONS(bvn)
```
3. Issue the following DFSMShsm command to create a replacement backup version of the data set:
```
BACKDS dsname
```

An optional first step might be appropriate if the number of backup versions on the migration volume is large or if the original data sets no longer exist from which to create new backup versions. The movement of the backup versions phase of automatic backup, run in the primary DFSMShsm host, moves all of the valid backup versions to backup volumes. Allowing automatic backup to run first moves all backup versions off all ML1 volumes so that only the MCM records for the damaged volume must be examined. The remainder of the procedure must still be followed for lost backup versions. If the migration volume was dumped, backup versions might have been lost if placed on the migration volume after the dump copy was created. If the migration volume was not restored from a dump copy, backup versions could still be lost if they resided on the parts of the volume that were damaged.