SAP Note 21551 - Log files are not released despite backup

Symptom:

After performing a backup of the logical log files, several log files are still not available.
The status flags of these log files are set as follows: "U-B----" ('onstat -l').

Cause and prerequisites

Not an error.

Solution
To maintain the consistency of the data, there are two cases in which a logical log file is not released immediately, although it has been backed up.

1. The logical log file contains log information for a transaction
that has not yet been completed with a COMMIT or ROLLBACK.
2. The log file contains the last checkpoint.

As soon as neither of the above conditions is true, the log file is released.

For an exact description of the logical log and its handling, please refer to the INFORMIX Administration manual.

NOTE: Starting with INFORMIX Version 7.10.UD1 the 'onstat -l' output
has changed (for this refer to note 40220).

Additional key words

onstat, logical log