This issue occurs due to additional security constraints added in version 6.4.3.3. 
This document references the support tool SLAnalyzer.. For more information see: What is SLAnalyzer? 

Text highlited in yellow/orange are commands entered into the terminal/console window.

To identify the issue use SLAnalyzer, the server console, or an SSH session.

From SLAnalyzer select: Tools->Common Appliance Framework->Check docker container status

From the VM console or SSH session:
docker ps -a --format='table {{.Names}}\t{{.Status}}'

If the status of the docker image audb is restarting, check the docker logs of the container to determine the cause of the failure.

To check the docker logs with SLAnalyzer: Tools->Common Appliance Framework->Get docker log
Select the docker log aaf_audb_1 or aaf-audb-1

docker logs --tail 200 aaf_audb_1
PostgreSQL Database directory appears to contain a database; Skipping initialization
2025-01-08 18:31:39.650 UTC [1] FATAL:  could not load server certificate file "/var/lib/postgresql/data/server-cert.pem": ee key too small
2025-01-08 18:31:39.650 UTC [1] LOG:  database system is shut down

This error indicates that the public key for the certificate server-cert.pem is too small. The minimum size is now 2048. So this certificate needs to be recreated with the correct size.

Checking the aucore container logs shows:

docker logs --tail 200 aaf_aucore_1
(Background on this error at: https://sqlalche.me/e/14/e3q8)
2025-01-08 18:32:01 WARNI [aucore.scripts.wait_db] DB is not ready2025-01-08 18:32:04 WARNI [aucore.scripts.wait_db] (psycopg2.OperationalError) connection to server at "127.0.0.1", port 5432 failed: Connection refused
        Is the server running on that host and accepting TCP/IP connections?
(Background on this error at: https://sqlalche.me/e/14/e3q8)
2025-01-08 18:32:04 WARNI [aucore.scripts.wait_db] DB is not ready

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