During the CATTRS process, a CAT4541I message is issued.
Cause
When this message is issued.
A gap was detected in the edit of GDG data sets. The GDG that is missing is the generation between the levels that are reported. This message serves only as a warning that a data set is not being processed for retention/movement. It may have been inadvertently scratched, or may be out-of-service.
The message is issued because some of the data sets (those that are missing) are not FILESEQ=0001 but generally FILESEQ NOT= 0001. TLMSTRS only looks at the CDS, by default FILESEQ=0001, for retention. Therefore, since we only look at the CDS, any volumes that do not have this file as FILESEQ=0001 will be controlled by some other retention criteria.
The position in the cycle is determined by create date and time. This is then checked against the generation number if the volume is a GDG to verify that they are also in order by creation date and time. The creation date and time check requires that a higher gdg generation be created after the previous generation, if not a warning is issued to alert the tape librarian.
Resolution
It is just a warning and can be ignored. The solution is to suppress the messages using a CMSG parameter in TLMSIPO (CMSG=CAT4541I,MSG=SUP).