Managing Quorum Devices

The quorum device service must be managed from the host system where the quorum device service is running.

Quorum configuration for the cluster and the configuration of the quorum device on the cluster nodes is performed by running operations on any of the nodes within the cluster itself.

Controlling the Quorum Device Service

You can perform various operations to directly control the quorum device service. Commands that control the quorum device service must be run on the host where the quorum device service is running.

To view the full status for the service, run:

sudo pcs qdevice status net --full

Output similar to the following is displayed:

QNetd address:                  *:5403
TLS:                            Supported (client certificate required)
Connected clients:              2
Connected clusters:             1
Maximum send/receive size:      32768/32768 bytes
Cluster "test":
    Algorithm:          ffsplit
    Tie-breaker:        Node with lowest node ID
    Node ID 2:
        Client address:         ::ffff:192.168.2.25:33526
        HB interval:            8000ms
        Configured node list:   1, 2
        Ring ID:                1.16
        Membership node list:   1, 2
        TLS active:             Yes (client certificate verified)
        Vote:                   ACK (ACK)
    Node ID 1:
        Client address:         ::ffff:192.168.2.26:48786
        HB interval:            8000ms
        Configured node list:   1, 2
        Ring ID:                1.16
        Membership node list:   1, 2
        TLS active:             Yes (client certificate verified)
        Vote:                   ACK (ACK)

To start the service, run:
```
sudo pcs qdevice start net
```
To stop the service, run:
```
sudo pcs qdevice stop net
```
To enable the service so that it runs at boot time, run:
```
sudo pcs qdevice enable net
```
To disable the service to prevent it from restarting at boot, run:
```
sudo pcs qdevice disable net
```
To force the service to stop if the normal stop process is not working, run:
```
sudo pcs qdevice kill net
```

Updating Quorum Device Settings

The quorum device can be updated in the cluster configuration at any time. Modifications to the quorum device configuration must be performed on a node within the cluster. Typically modifications to the quorum device involve changing the algorithm, however you can modify other options that are available for a quorum device in the same way.

To update the algorithm used for the quorum device, run:

sudo pcs quorum device update model algorithm=lms

The example changes the algorithm to use the lms or last-man-standing algorithm.

Note:

You can't update the host for a quorum device. You must remove the device and add it back into the cluster if you need to change the host.

Removing the Quorum Device From the Cluster

To remove the quorum device from the cluster, run the following command on a node within the cluster:

sudo pcs quorum device remove

Removing the quorum device updates the cluster configuration to remove any configuration entries for the quorum device, reloads the cluster configuration into the cluster and then disables and stops the quorum device on each node.

Because you might use the same quorum device service across multiple clusters, removing the quorum device from the cluster doesn't affect the quorum device service in any way. The service continues to run on the service host, but no longer serves the cluster where it has been removed.

Destroying the Quorum Device Service

You can destroy the quorum device service on the host where the service is running. This action stops the service and removes any configuration for the service from the host.

sudo pcs qdevice destroy net

Note:

Remove the quorum device from any clusters that it services before destroying the quorum device service.