Creating a libvirt Cluster

4 Creating a libvirt Cluster

Create a Kubernetes cluster using the libvirt provider.

(Optional) Set up a cluster configuration file.
A cluster configuration contains the cluster specific information to use when creating the cluster. Use a cluster configuration file to override cluster defaults, or you can use ocne cluster start command options to configure a cluster. A cluster configuration file might include:
```
provider: libvirt
name: mycluster
workerNodes: 2
controlPlaneNodes: 1
providers:
  libvirt:
    controlPlaneNode:
      cpu: 2
      memory: 8Gi
      storage: 20Gi
    workerNode:
      cpu: 2
      memory: 8Gi
      storage: 20Gi
```
For information about cluster configuration files, see Oracle Cloud Native Environment: Kubernetes Clusters.

Create a libvirt cluster.

Use the ocne cluster start command to create a cluster. The syntax is:

ocne cluster start 
[{-u|--auto-start-ui} {true|false}]
[{-o|--boot-volume-container-image} URI]
[{-C|--cluster-name} name]
[{-c|--config} path] 
[{-n|--control-plane-nodes} integer] 
[{-i|--key} path]
[--load-balancer address]
[{-P|--provider} provider]
[{-s|--session} URI]
[{-v|--version} version]
[--virtual-ip IP]
[{-w|--worker-nodes} integer]

For more information on the syntax options, see Oracle Cloud Native Environment: CLI.

When you create a cluster on a remote system, include the session information in the format qemu+ssh://user@host/system where host is the name or IP address of the remote system. For example:

--session qemu+ssh://myuser@myhost.example.com/system

Example 4-1 Create a default cluster using the libvirt provider

To create a libvirt cluster, using all default settings:

ocne cluster start

Example 4-2 Create a libvirt cluster using a configuration file

To create a libvirt cluster using a configuration file:

ocne cluster start --config myconfig.yaml

Example 4-3 Create a libvirt cluster with specified nodes and virtual IP

To create a cluster with a specified number of worker and control plane nodes, and a virtual IP address:

ocne cluster start --control-plane-nodes 3 --worker-nodes 5 --virtual-ip 192.168.0.100

Example 4-4 Create a remote libvirt cluster using a configuration file

To create a cluster on a remote host using a configuration file:

ocne cluster start --session qemu+ssh://myuser@myhost.example.com/system --config myconfig.yaml