crm_verify

crm_verify is a command-line utility from the crmsh (Cluster Resource Manager Shell) toolkit used in Pacemaker-based clusters. Its primary purpose is to validate cluster configurations—typically the XML Cluster Information Base (CIB) file—to ensure that they are syntactically correct and consistent with the rules and constraints expected by Pacemaker.

Purpose

• Configuration Validation: crm_verify checks the cluster configuration (usually in XML format) for syntax errors and structural inconsistencies before it is applied. This helps catch errors that could lead to resource failures or cluster instability.

• Troubleshooting: By running crm_verify, administrators can identify misconfigurations or potential issues in the CIB. The tool provides diagnostic output that highlights errors and warnings, enabling corrective action before deployment.

• Pre-Deployment Check: Verifying the configuration with crm_verify before pushing changes to a live cluster can prevent downtime and ensure that the configuration meets all required standards.

Basic Syntax

crm_verify [options] [configuration-file]

• configuration-file: If provided, crm_verify will validate the specified XML file. If omitted, it may validate the currently active cluster configuration stored in the CIB.

Common Options

• -v or --verbose: Produce detailed output, which is useful for diagnosing problems in the configuration.

• --strict: Enable strict mode where warnings are treated as errors, ensuring a higher level of compliance with expected configuration standards.

Example Usage

1. Verify an XML Configuration File:

   crm_verify /path/to/cib.xml

   This command checks the specified CIB file for any syntax or consistency errors.

2. Verbose Verification:

   crm_verify -v /etc/cib.xml

   This provides a more detailed diagnostic output, useful for pinpointing specific issues in the configuration.

3. Validate Active Configuration: Running crm_verify without specifying a file may check the active configuration in the cluster’s CIB, depending on your environment’s setup.

Conclusion

crm_verify is a valuable tool for administrators managing Pacemaker clusters. By verifying that the cluster configuration is error-free and consistent, it helps prevent misconfigurations that could lead to service disruption. Running this tool before applying configuration changes is a best practice to ensure high availability and smooth cluster operations.