Introduction

The shared unattended switch and interactive workflow are described in environment modes.

Add Swap Memory

TIP

Adding some swap prevents the host from running out of memory.

Unit conversion: entering 1024 creates 1GB of SWAP virtual memory. Virtual memory uses disk space. When actual memory runs out, virtual memory is used automatically, but this brings high I/O and CPU usage.

It is recommended to create swap no larger than twice the actual memory size.

curl -L https://raw.githubusercontent.com/spiritLHLS/addswap/main/addswap.sh -o addswap.sh && chmod +x addswap.sh && bash addswap.sh

Kubelet swap handling depends on the K3s configuration. Check compatibility before enabling swap; it does not replace the minimum RAM requirement.

Environment Installation

export noninteractive=true
bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/kubevirt/main/kubevirtinstall.sh)

Defaults are K3s v1.34.12+k3s1, KubeVirt v1.9.1 and CDI v1.66.1. virtctl follows KUBEVIRT_VERSION unless VIRTCTL_VERSION is supplied. The administrator kubeconfig is created with mode 0600.

The installer places onevm.sh, create_vm.sh, listvms.sh, snapshotvm.sh, resizevm.sh, deletevm.sh and update-port-rules.sh in /usr/local/bin.

Local installation inputs for offline or unreliable networks:

export noninteractive=true
export K3S_INSTALL_SCRIPT=/path/to/k3s-install.sh
export KUBEVIRT_MANIFEST_DIR=/path/to/kubevirt-manifests
export CDI_MANIFEST_DIR=/path/to/cdi-manifests
export VIRTCTL_BINARY=/path/to/virtctl
export KUBEVIRT_SCRIPT_DIR=/path/to/kubevirt
bash kubevirtinstall.sh

These variables provide local inputs for the named installer stages. Cluster and guest container images must also be available to the target environment.

Environment variables

Variable	Description	Default
noninteractive	Shared unattended switch	unset
K3S_VERSION	K3s release	v1.34.12+k3s1
KUBEVIRT_VERSION	KubeVirt release	v1.9.1
CDI_VERSION	CDI release	v1.66.1
VIRTCTL_VERSION	virtctl release	follows KUBEVIRT_VERSION
K3S_INSTALL_SCRIPT	Local K3s installer	unset
KUBEVIRT_MANIFEST_DIR	Local directory containing kubevirt-operator.yaml and kubevirt-cr.yaml	unset
CDI_MANIFEST_DIR	Local directory containing cdi-operator.yaml and cdi-cr.yaml	unset
KUBEVIRT_OPERATOR_YAML / KUBEVIRT_CR_YAML	Explicit local KubeVirt operator/CR manifests	unset
CDI_OPERATOR_YAML / CDI_CR_YAML	Explicit local CDI operator/CR manifests	unset
VIRTCTL_BINARY	Local virtctl executable	unset
KUBEVIRT_SCRIPT_DIR	Local scripts, such as firewall.sh and onevm.sh	unset
K3S_IP_FAMILY	auto, ipv4 or dualstack	auto
K3S_CLUSTER_CIDR / K3S_SERVICE_CIDR	Override pod and Service CIDRs for a new dual-stack cluster	10.42.0.0/16,fd42:42::/56 / 10.43.0.0/16,fd42:43::/112
KUBEVIRT_INSTALL_MULTUS	Install the K3s/Flannel Multus secondary-interface entry point	false
SSH_READY_TIMEOUT	Password SSH and cloud-init verification budget in seconds	600
KEEP_FAILED_RESOURCES	Preserve resources on supported creation failure paths for diagnosis	false
STORE_PASSWORD_ANNOTATION	Store a plaintext password in VM metadata	false
DELETE_SNAPSHOTS	Delete snapshot DataVolumes with the VM	false
ALLOW_RUNNING_SNAPSHOT	Allow cloning a running VM's disk	false
WAIT_SNAPSHOT	Wait for the DataVolume clone	true
RESTART_VM	Restart after changing VM resources	false
SHOW_PASSWORD	Show passwords available in VM annotations or local vmlog	false

Uninstall KubeVirt Environment

This removes the KubeVirt/K3s environment and its workloads. Back up data first; noninteractive=true skips confirmation.

export noninteractive=true
bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/kubevirt/main/kubevirtuninstall.sh)

Verify installation

kubectl get pods -n kubevirt

For long installations, use screen or tmux to avoid interruption when SSH disconnects.