Chapter 8. Ceph debugging and logging configuration

As a storage administrator, you can increase the amount of debugging and logging information to help diagnose problems with the Red Hat Ceph Storage.

8.1. Prerequisites

  • Installation of the Red Hat Ceph Storage software.

8.2. Ceph debugging and logging

Debug settings are NOT required in the Ceph configuration file, but can be added to optimize logging. Changes to the Ceph logging configuration usually occur at runtime when a problem occurs, but may also be modified in the Ceph configuration file. For example, if there are issues when starting the cluster, consider increasing log settings in the Ceph configuration file. When the problem is resolved, remove the settings or restore them to optimal settings for runtime operations.

By default, view Ceph log files under /var/log/ceph.

Tip

When debug output slows down the cluster, the latency can hide race conditions.

Logging is resource intensive. If there is a problem in a specific area of the cluster, enable logging for that area of the cluster. For example, if OSDs are running fine but Ceph Object Gateways are not, start by enabling debug logging for the specific gateway instances encountering problems. Increase or decrease logging for each subsystem as needed.

Important

Verbose logging can generate over 1GB of data per hour. If the OS disk reaches its capacity, the node will stop working.

If Ceph logging is enabled or the rate of logging increased, ensure that the OS disk has sufficient capacity.

When the cluster is running well, remove unnecessary debugging settings to ensure the cluster runs optimally. Logging debug output messages is relatively slow, and a waste of resources when operating your cluster.

8.3. Additional Resources

  • See all the Red Hat Ceph Storage Ceph debugging and logging configuration options in Appendix J for specific option descriptions and usage.