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

Unattended operation

All scripts accept:

export noninteractive=true

Installation and batch creation use defaults or supplied arguments without waiting for input. Deletion and uninstallation treat this variable as explicit confirmation. Existing per-script variables such as VM_COUNT, QEMU_FORCE_DELETE and QEMU_FORCE_UNINSTALL remain supported.

Environment Installation

bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/qemu/main/qemuinstall.sh)

Unattended installation with a custom image directory:

export noninteractive=true
export QEMU_IMAGES_PATH=/data/vm-images
bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/qemu/main/qemuinstall.sh)

The default image directory is /var/lib/libvirt/images.

Environment variables

Script	Variable	Description	Example
All	noninteractive	Shared unattended switch	true
qemuinstall.sh	QEMU_IMAGES_PATH	Image storage directory	/data/images
qemuuninstall.sh	QEMU_FORCE_UNINSTALL	Skip uninstall confirmation	yes
oneqemu.sh	VM_NAME	VM name	vm1
oneqemu.sh	VM_CPU	CPU cores	1
oneqemu.sh	VM_MEMORY	Memory in MB	1024
oneqemu.sh	VM_DISK	Disk size in GB	20
oneqemu.sh	VM_PASSWORD	Root password; empty generates one	ChangeMe-123
oneqemu.sh	VM_SSH_PORT	SSH host port	25001
oneqemu.sh	VM_START_PORT	First additional port	35001
oneqemu.sh	VM_END_PORT	Last additional port	35025
oneqemu.sh	VM_SYSTEM	Guest OS	debian12
create_qemu.sh	VM_COUNT	Number of VMs	3
create_qemu.sh	VM_MEMORY	Memory per VM in MB	1024
create_qemu.sh	VM_CPU	CPU cores per VM	1
create_qemu.sh	VM_DISK	Disk size per VM in GB	20
create_qemu.sh	VM_SYSTEM	Guest OS	debian12
delete_qemu.sh	VM_NAME	VM to delete	vm1
delete_qemu.sh	QEMU_FORCE_DELETE	Skip deletion confirmation	yes

Uninstall QEMU/KVM Environment

Remove all VMs, images, network settings, systemd services and QEMU/KVM packages:

bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/qemu/main/qemuuninstall.sh)

The script asks for yes; removal is irreversible. To skip confirmation:

export noninteractive=true
export QEMU_FORCE_UNINSTALL=yes
bash <(curl -sSL https://raw.githubusercontent.com/oneclickvirt/qemu/main/qemuuninstall.sh)

Alternatively, after downloading the script, run curl -sSL https://raw.githubusercontent.com/oneclickvirt/qemu/main/qemuuninstall.sh -o qemuuninstall.sh bash qemuuninstall.sh -y.

Verify installation

virsh list --all

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