13.1 Server and Database Operations

machadmin starts and stops server instances, creates and drops physical databases, installs licenses, and performs offline restores. Distinguish logical databases created with SQL CREATE DATABASE from the physical instance database created with machadmin -c.

Check the main options

"$MACHBASE_HOME/bin/machadmin" -h

Use the help for the installed release to check options and their effects.

Start and stop the server

You can safely run the status check.

"$MACHBASE_HOME/bin/machadmin" -e

Use one consistent method to start and stop the server: a service manager or your operations runbook.

• Before startup, check the configuration, license, data paths, and free space.
• After startup, check machadmin -e, a connection on port 5656, a lightweight SQL query, and server logs.
• Before a normal shutdown, block new connections and ingestion, and check active transactions, backups, and Appenders.
• Use a forced shutdown only after normal shutdown repeatedly fails and you have assessed the recovery impact.
• Do not force a recovery mode arbitrarily. Check the error and documented recovery procedure.

Command output can vary by release. Do not make automation depend on a complete success message. Check both the process exit code and an actual connection.

Physical instance database

machadmin -c and machadmin -d create and delete physical instance data in DBS_PATH. For logical databases, use the SQL described in Multiple Databases.

Deleting or initializing a physical database is destructive and can lose all instance data. Do not delete and recreate a database to resolve a server startup error. Diagnose the error first, then choose a recovery method that preserves the existing data.

Before execution, verify:

1. The absolute paths of the target MACHBASE_HOME and DBS_PATH.
2. That the service and processes have fully stopped.
3. A recent backup and a verified restore in an isolated environment.
4. The configuration, licenses, and logs to preserve.
5. Whether rollback is possible and the expected recovery time.
6. That two operators have cross-checked the instance and paths.

Do not manually create, move, or delete internal files or metadata in the data directory.

Install and verify a license

Treat license files as secrets. Do not copy their contents or actual keys into documentation, support requests, or logs.

SELECT *
FROM V$LICENSE_INFO;

Before installation, check the target instance, edition, validity period, and file permissions. For online installation, the server process must be able to read the path. After renewal, verify a new connection and the required edition features, and apply your retention policy to the original license file.

Information needed to diagnose failures

• machadmin -e output and exit code
• Release, edition, and MACHBASE_HOME
• Actual configuration and data paths
• Server startup and shutdown times
• Server logs around the first error
• File system free space and permissions
• Recent configuration, license, or storage changes

Do not delete the physical database or start with an initialization-based recovery merely because the server will not start. Preserve backups while diagnosing the cause.