What causes ORA-01033?

The Oracle instance is in the middle of startup (MOUNT or OPEN stage not complete). A DBA issued SHUTDOWN and the database is still closing. Oracle crashed and is performing automatic instance recovery. Maintenance window is in progress

How do I fix ORA-01033?

Step 1: Wait for Oracle to finish starting up and retry the connection.. Step 2: Check instance status from a DBA session: `SELECT status FROM v$instance;`.. Step 3: If startup is taking unusually long, check the alert log for recovery or media recovery messages.. Step 4: Add retry logic to the pipeline with exponential backoff to handle scheduled maintenance windows.. Step 5: Monitor Oracle availability with a health check before pipeline start.

Critical severityconnectivity

Oracle Database Error:
ORA-01033

What does this error mean?

Oracle is starting up or shutting down and is not yet ready to accept connections.

Common causes

1The Oracle instance is in the middle of startup (MOUNT or OPEN stage not complete)
2A DBA issued SHUTDOWN and the database is still closing
3Oracle crashed and is performing automatic instance recovery
4Maintenance window is in progress

How to fix it

1Step 1: Wait for Oracle to finish starting up and retry the connection.
2Step 2: Check instance status from a DBA session: `SELECT status FROM v$instance;`.
3Step 3: If startup is taking unusually long, check the alert log for recovery or media recovery messages.
4Step 4: Add retry logic to the pipeline with exponential backoff to handle scheduled maintenance windows.
5Step 5: Monitor Oracle availability with a health check before pipeline start.

Example log output

ORA-01033: ORACLE initialization or shutdown in progress

Frequently asked questions

How long should I wait before retrying?

Oracle startup typically takes 30 seconds to a few minutes. For crash recovery, it can take longer. Implement exponential backoff starting at 30 seconds with a cap of 10 minutes.

Source · docs.oracle.com/error-help/db/ora-01033