Host Management

Users can view and manage Harvester nodes from the host page. The first node always defaults to be a management node of the cluster. When there are three or more nodes, the two other nodes that first joined are automatically promoted to management nodes to form a HA cluster.

note

Because Harvester is built on top of Kubernetes and uses etcd as its database, the maximum node fault toleration is one when there are three management nodes.

Node Maintenance

Admin users can enable Maintenance Mode (select ⋮ > Enable Maintenance Mode) to automatically evict all virtual machines from a node. This mode leverages the live migration feature to migrate the virtual machines to other nodes, which is useful when you need to reboot, upgrade firmware, or replace hardware components. At least two active nodes are required to use this feature.

Cordoning a Node

Cordoned nodes are marked as unschedulable. Cordoning is useful when you want to prevent new workloads from being scheduled on a node. You can uncordon a node to make it schedulable again.

Deleting a Node

Deleting a node is done in two phases:

1. Delete the node from Harvester

   • Go to the Hosts page
   • On the node you want to modify, click ⋮ > Delete

2. Uninstall RKE2 from the node

   • Login to the node as root
   • Run rke2-uninstall.sh to delete the whole RKE2 service.

caution

You will lose all data of the control plane node after deleting the RKE2 service.

note

There's a known issue about node hard delete. Once resolved, the last step can be skipped.

Multi-disk Management - Tech Preview

Users can view and add multiple disks as additional data volumes from the host detail page.

1. Go to the Hosts page.
2. On the node you want to modify, click ⋮ > Edit Config.
3. Select the Disks tab and click Add Disks.
4. Select an additional raw block device to add as an additional data volume.
   • The Force Formatted option is required if the block device has never been force-formatted.

note

In order for Harvester to identify the disks, each disk needs to have a unique WWN. Otherwise, Harvester will refuse to add the disk. If your disk does not have a WWN, you can format it with the EXT4 filesystem to help Harvester recognize the disk.

note

If you are testing Harvester in a QEMU environment, you'll need to use QEMU v6.0 or later. Previous versions of QEMU will always generate the same WWN for NVMe disks emulation. This will cause Harvester to not add the additional disks, as explained above.