2Disbanding Clusters; 3Exchanging A Device; Diagnostics And Troubleshooting; 1Logging - CheckMK rack1 Mark III Manual

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13.6.2 Disbanding clusters
It is possible to disband the nodes from a cluster and continue running them separately. When doing so
you can continue using the synchronised configuration on both devices, or reset one of the devices to
factory settings and reconfigure it for example.
You can remove one or both nodes from the cluster during operation. If you wish to use both nodes, you
must ensure that the data synchronisation is in good working order beforehand. You can verify this on
the cluster page.
In order to disband a cluster, click on Disband cluster on the cluster page of the web interface. Read
the text of the confirm prompt that follows. In the different situations, this text contains information as
to the state the respective device is in after the disconnection.
The disconnection of the devices must be carried out on both nodes separately, so that both devices can
be run separately in future.
If you only wish to use one of the devices in future, disconnect the cluster on the device you intend to
continue using and then restore the factory settings on the other device.
Once you have disconnected a node from the cluster, the monitoring instances will not be started auto-
matically. If you wish to start the monitoring instances, you need to do so next via the web interface.
13.6.3 Exchanging a device
If the hard drives of the old device are in good order, you can take these from the old device and insert
them into the new device, wiring the new device in exactly the same way as the old device was wired
and then switching it on. After starting, the new device will merge into the cluster in the same way as
the old device.
If you want to completely replace an old device with a new one, you should proceed in the same way as
when disbanding the cluster completely (see previous chapter). To do this, select one of the previous
devices, disconnect this device from the cluster and create a new cluster with this device and the new
device.

13.7 Diagnostics and troubleshooting

13.7.1 Logging
Cluster administration is a largely automatic function, whereby automatic processes on the nodes decide
which device which resources are to be started and stopped on. This behaviour is logged in the form of
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