C Cluster Management Tools (Command Line) #
SUSE Linux Enterprise High Availability ships with a comprehensive set of tools to assists you in managing your cluster from the command line. This chapter introduces the tools needed for managing the cluster configuration in the CIB and the cluster resources. Other command line tools for managing resource agents or tools used for debugging (and troubleshooting) your setup are covered in Appendix A, Troubleshooting.
This tool is for experts only. Usually the crm shell (crmsh) is the recommended way of managing your cluster.
The following list presents several tasks related to cluster management and briefly introduces the tools to use to accomplish these tasks:
- Monitoring the Cluster's Status
The
crm_mon
command allows you to monitor your cluster's status and configuration. Its output includes the number of nodes, uname, UUID, status, the resources configured in your cluster, and the current status of each. The output ofcrm_mon
can be displayed at the console or printed into an HTML file. When provided with a cluster configuration file without the status section,crm_mon
creates an overview of nodes and resources as specified in the file. See thecrm_mon
man page for a detailed introduction to this tool's usage and command syntax.- Managing the CIB
The
cibadmin
command is the low-level administrative command for manipulating the CIB. It can be used to dump all or part of the CIB, update all or part of it, modify all or part of it, delete the entire CIB, or perform miscellaneous CIB administrative operations. See thecibadmin
man page for a detailed introduction to this tool's usage and command syntax.- Managing Configuration Changes
The
crm_diff
command assists you in creating and applying XML patches. This can be useful for visualizing the changes between two versions of the cluster configuration or saving changes so they can be applied at a later time usingcibadmin
. See thecrm_diff
man page for a detailed introduction to this tool's usage and command syntax.- Manipulating CIB Attributes
The
crm_attribute
command lets you query and manipulate node attributes and cluster configuration options that are used in the CIB. See thecrm_attribute
man page for a detailed introduction to this tool's usage and command syntax.- Validating the Cluster Configuration
The
crm_verify
command checks the configuration database (CIB) for consistency and other problems. It can check a file containing the configuration or connect to a running cluster. It reports two classes of problems. Errors must be fixed before the High Availability software can work properly while warning resolution is up to the administrator.crm_verify
assists in creating new or modified configurations. You can take a local copy of a CIB in the running cluster, edit it, validate it usingcrm_verify
, then put the new configuration into effect usingcibadmin
. See thecrm_verify
man page for a detailed introduction to this tool's usage and command syntax.- Managing Resource Configurations
The
crm_resource
command performs various resource-related actions on the cluster. It lets you modify the definition of configured resources, start and stop resources, or delete and migrate resources between nodes. See thecrm_resource
man page for a detailed introduction to this tool's usage and command syntax.- Managing Resource Fail Counts
The
crm_failcount
command queries the number of failures per resource on a given node. This tool can also be used to reset the fail count, allowing the resource to again run on nodes where it had failed too often. See thecrm_failcount
man page for a detailed introduction to this tool's usage and command syntax.- Managing a Node's Standby Status
The
crm_standby
command can manipulate a node's standby attribute. Any node in standby mode is no longer eligible to host resources and any resources that are there must be moved. Standby mode can be useful for performing maintenance tasks, such as Kernel updates. Remove the standby attribute from the node for it to become a fully active member of the cluster again. See thecrm_standby
man page for a detailed introduction to this tool's usage and command syntax.