Problem summary: updating of some older records failed, because they were created by some older jobs that did not complete successfully. Such records were tied to an entity that stored metadata about the job, and the status of that metadata entity was incorrect due to some troubles with updating the status (it could have happened at the time that mod-source-record-storage was unavailable). As a result, newly imported records for update couldn't be saved in mod-source-record-storage with updated generation.

Resolution:

1. The issue can be resolved on the DB side of mod-source-record-storage - every Snapshot status other than COMMITTED should be set to ERROR in the snapshots_lb table. For future releases (Iris Hot Fix #3, Juniper Bugfix) Folijet will add a migration script to ensure that the data in mod-source-record-storage is correct and there are no invalid job/snapshot statuses.

2. Add note to https://folio-org.atlassian.net/wiki/display/REL/R1+2021+%28Iris%29+Release+Notes about the possible cleanup that is needed and the script