Managing Oracle Clusterware (CRS)

Essential commands for starting, stopping, checking, and monitoring CRS services.

Note: Start/stop need to be run as root from the CRS home.

SQL Code

Start CRS

1crsctl start crs

Stop CRS

1crsctl stop crs

Check CRS's status

1crsctl check crs

See the status of the various services

1crs_stat -t

Sample Oracle Output:

2no rows selected

Description of the Oracle Database SQL code:


  • To manage the lifecycle and monitor the health of Oracle Clusterware (CRS), the foundational infrastructure for Oracle Real Application Clusters (RAC) and other high availability solutions.

Breakdown of Commands:

  1. crsctl start crs

    • Purpose: Initiates the startup of CRS on all nodes in the cluster.

    • Key Points:

      • Crucial for restoring CRS functionality after planned or unplanned outages.
      • Might require root privileges depending on configuration.
  2. crsctl stop crs

    • Purpose: Gracefully shuts down CRS on all nodes, typically for maintenance or troubleshooting.

    • Key Points:

      • Ensures orderly shutdown of CRS resources and services.
      • Should be used cautiously as it impacts database availability.
  3. crsctl check crs

    • Purpose: Verifies the current status of CRS, including its overall health and the state of individual resources.

    • Key Points:

      • Provides a quick overview of CRS health.
      • Helps identify potential issues or inconsistencies.
  4. crs_stat -t

    • Purpose: Displays a detailed status of CRS resources and services, including their names, states, and dependencies.

    • Key Points:

      • Offers a more granular view of CRS components for in-depth analysis.
      • Useful for troubleshooting specific issues or monitoring resource usage.

Insights and Explanations:

  • Essential for High Availability: CRS is vital for managing cluster resources and ensuring high availability in Oracle RAC environments.
  • Root Privileges: Some commands might require root privileges, depending on system configuration.
  • Planned Maintenance: Use crsctl stop crs and crsctl start crs for planned maintenance or software updates.
  • Troubleshooting: crsctl check crs and crs_stat -t are valuable tools for diagnosing and resolving CRS-related issues.
  • Regular Monitoring: Regularly monitor CRS status to proactively identify and address potential problems.
  • Additional Commands: CRS provides a rich set of commands for managing various aspects of the cluster, such as resource management, configuration, and logging.

Posts in this series