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6.3.2. Managing HA Services with `clusvcadm`

You can manage HA services using the clusvcadm command. With it you can perform the following operations:

Enable and start a service.
Disable a service.
Stop a service.
Freeze a service
Unfreeze a service
Migrate a service (for virtual machine services only)
Relocate a service.
Restart a service.

Table 6.2, “Service Operations” describes the operations in more detail. For a complete description on how do perform those operations, refer to the clusvcadm utility man page.

Table 6.2. Service Operations

Service Operation	Description	Command Syntax
Enable	Start the service, optionally on a preferred target and optionally according to failover domain rules. In absence of either, the local host where `clusvcadm` is run will start the service. If the original start fails, the service behaves as though a relocate operation was requested (refer to Relocate in this table). If the operation succeeds, the service is placed in the started state.	`clusvcadm -e <service_name>` or `clusvcadm -e <service_name> -m <member>` (Using the -m option specifies the preferred target member on which to start the service.)
Disable	Stop the service and place into the disabled state. This is the only permissible operation when a service is in the failed state.	`clusvcadm -d <service_name>`
Relocate	Move the service to another node. Optionally, you may specify a preferred node to receive the service, but the inability of the service to run on that host (for example, if the service fails to start or the host is offline) does not prevent relocation, and another node is chosen. `rgmanager` attempts to start the service on every permissible node in the cluster. If no permissible target node in the cluster successfully starts the service, the relocation fails and the service is attempted to be restarted on the original owner. If the original owner cannot restart the service, the service is placed in the stopped state.	`clusvcadm -r <service_name>` or `clusvcadm -r <service_name> -m <member>` (Using the -m option specifies the preferred target member on which to start the service.)
Stop	Stop the service and place into the stopped state.	`clusvcadm -s <service_name>`
Freeze	Freeze a service on the node where it is currently running. This prevents status checks of the service as well as failover in the event the node fails or rgmanager is stopped. This can be used to suspend a service to allow maintenance of underlying resources. Refer to the section called “Considerations for Using the Freeze and Unfreeze Operations” for important information about using the freeze and unfreeze operations.	`clusvcadm -Z <service_name>`
Unfreeze	Unfreeze takes a service out of the freeze state. This re-enables status checks. Refer to the section called “Considerations for Using the Freeze and Unfreeze Operations” for important information about using the freeze and unfreeze operations.	`clusvcadm -U <service_name>`
Migrate	Migrate a virtual machine to another node. You must specify a target node. Depending on the failure, a failure to migrate may result with the virtual machine in the failed state or in the started state on the original owner.	`clusvcadm -M <service_name> -m <member>` Important For the migrate operation, you must specify a target node using the `-m <member>` option.
Restart	Restart a service on the node where it is currently running.	`clusvcadm -R <service_name>`

Considerations for Using the Freeze and Unfreeze Operations

Using the freeze operation allows maintenance of parts of rgmanager services. For example, if you have a database and a web server in one rgmanager service, you may freeze the rgmanager service, stop the database, perform maintenance, restart the database, and unfreeze the service.

When a service is frozen, it behaves as follows:

Status checks are disabled.
Start operations are disabled.
Stop operations are disabled.
Failover will not occur (even if you power off the service owner).

Important

Failure to follow these guidelines may result in resources being allocated on multiple hosts:

You must not stop all instances of rgmanager when a service is frozen unless you plan to reboot the hosts prior to restarting rgmanager.
You must not unfreeze a service until the reported owner of the service rejoins the cluster and restarts rgmanager.

6.3.2. Managing HA Services with clusvcadm

Table 6.2. Service Operations

Important

Considerations for Using the Freeze and Unfreeze Operations

Important

6.3.2. Managing HA Services with `clusvcadm`