Keycloak stuck at AStquerytranslatorfactory and not able to start

Question

We are trying to start keycloak server and it is stuck AStquerytranslatorfactory and not starting.

The server is not starting and it is stuck at the same place. We tried to turn on debug logging but that does not help as they logs go back to INFO level

Answer 1

ASTQueryTranslatorFactory is a Hibernate class that generates SQL from structured formats like HQL, Hibernate Criteria queries or JPQL. Keycloak server stuck after a line that refers to this class is an indication that a database operation is in progress.

The following steps are suggested without knowing exact details of Keycloak version, operating systems, etc.

Step 1: Database change logs

Keycloak attempts to perform in-place database schema upgrade upon startup. It uses a table named DATABASECHANGELOGLOCK to obtain a lock on the schema.

Check this table and see if a lock exists in this table. If this is the case, find out which process holds the lock at the moment and see if the lock can be manually freed. The exact mechanism for this depends on the database used and the version.

Step 2: Table locks

It is also possible that a run-off process holds a lock on a table required by Keycloak. The exact mechanism again depends on the database used. If this is the case, see if the lock can be freed.

Step 3: Offline user sessions

Keycloak attempts to load records from the table named OFFLINE_USER_SESSION at startup. Check how many records exist in this table. If this is the case, you are unfortunately stuck. As described here, here and here, this is a known problem.

If you find yourself in this situation, you will either have to wait until Keycloak finishes loading offline sessions in memory, or you can clear the table temporarily, bring Keycloak up and restore the table after that.