Restoring a damaged PDS

During a logical restore, a PDS is monitored by DFSMSdss for conditions that are not normal. The following conditions are detected and reported:

Missing high-key entry in the PDS directory
Missing directory EOF
Invalid member start TTR:
- TTR points before directory EOF
- TTR points after end of data set
Missing member EOF. Each member of a partitioned data set is normally terminated by an EOF record.
Invalid note or note list TTR:
- Note pointing before the start of member data
- Note pointing after the member EOF
- Note pointing past the last valid record on a track
- Note pointing to record 0 of a track

DFSMSdss notes all of these conditions with a message.

During compression, DFSMSdss repairs all missing high-key directory entries, missing directory EOFs, and missing member EOFs.

Invalid start TTRs prevent DFSMSdss from compressing data for that member. DFSMSdss translates all valid note and note list TTRs during compression.

Use the NOPACKING keyword to restore damaged partitioned data sets to same or like device target volumes. This results in an exact track-for-track image of the source data set. Obviously, no compression is performed in this case. During physical restore operations, DFSMSdss uses only track-level I/O. Therefore, no compression takes place against the PDS.