packer-cn/website/content/docs/builders/qemu.mdx

---
modeline: |
  vim: set ft=pandoc:
description: |
  The Qemu Packer builder is able to create KVM virtual machine images.
page_title: QEMU - Builders
sidebar_title: QEMU
---

# QEMU Builder

Type: `qemu`

The Qemu Packer builder is able to create [KVM](http://www.linux-kvm.org) virtual
machine images.

The builder builds a virtual machine by creating a new virtual machine from
scratch, booting it, installing an OS, rebooting the machine with the boot media
as the virtual hard drive, provisioning software within the OS, then shutting it
down. The result of the Qemu builder is a directory containing the image file
necessary to run the virtual machine on KVM.

## Basic Example

Here is a basic example. This example is functional so long as you fixup paths
to files, URLS for ISOs and checksums.

<Tabs>
<Tab heading="JSON">

```json
{
  "builders": [
    {
      "type": "qemu",
      "iso_url": "http://mirror.raystedman.net/centos/6/isos/x86_64/CentOS-6.9-x86_64-minimal.iso",
      "iso_checksum": "md5:af4a1640c0c6f348c6c41f1ea9e192a2",
      "output_directory": "output_centos_tdhtest",
      "shutdown_command": "echo 'packer' | sudo -S shutdown -P now",
      "disk_size": "5000M",
      "format": "qcow2",
      "accelerator": "kvm",
      "http_directory": "path/to/httpdir",
      "ssh_username": "root",
      "ssh_password": "s0m3password",
      "ssh_timeout": "20m",
      "vm_name": "tdhtest",
      "net_device": "virtio-net",
      "disk_interface": "virtio",
      "boot_wait": "10s",
      "boot_command": [
        "<tab> text ks=http://{{ .HTTPIP }}:{{ .HTTPPort }}/centos6-ks.cfg<enter><wait>"
      ]
    }
  ]
}
```

</Tab>
<Tab heading="HCL2">

```hcl
source "qemu" "example" {
  iso_url           = "http://mirror.raystedman.net/centos/6/isos/x86_64/CentOS-6.9-x86_64-minimal.iso"
  iso_checksum      = "md5:af4a1640c0c6f348c6c41f1ea9e192a2"
  output_directory  = "output_centos_tdhtest"
  shutdown_command  = "echo 'packer' | sudo -S shutdown -P now"
  disk_size         = "5000M"
  format            = "qcow2"
  accelerator       = "kvm"
  http_directory    = "path/to/httpdir"
  ssh_username      = "root"
  ssh_password      = "s0m3password"
  ssh_timeout       = "20m"
  vm_name           = "tdhtest"
  net_device        = "virtio-net"
  disk_interface    = "virtio"
  boot_wait         = "10s"
  boot_command      = ["<tab> text ks=http://{{ .HTTPIP }}:{{ .HTTPPort }}/centos6-ks.cfg<enter><wait>"]
}

build {
  sources = ["source.qemu.example"]
}
```

</Tab>
</Tabs>

This is an example only, and will time out waiting for SSH because we have not
provided a kickstart file. You must add a valid kickstart file to the
"http_directory" and then provide the file in the "boot_command" in order for
this build to run. We recommend you check out the
[Community Templates](/community-tools#templates)
for a practical usage example.

Note that you will need to set `"headless": true` if you are running Packer
on a Linux server without X11; or if you are connected via ssh to a remote
Linux server and have not enabled X11 forwarding (`ssh -X`).

## Qemu Specific Configuration Reference

There are many configuration options available for the builder. In addition to
the items listed here, you will want to look at the general configuration
references for [ISO](#iso-configuration),
[HTTP](#http-directory-configuration),
[Floppy](#floppy-configuration),
[Boot](#boot-configuration),
[Shutdown](#shutdown-configuration),
[Communicator](#communicator-configuration)
configuration references, which are
necessary for this build to succeed and can be found further down the page.

### Optional:

@include 'builder/qemu/Config-not-required.mdx'

## ISO Configuration

@include 'packer-plugin-sdk/multistep/commonsteps/ISOConfig.mdx'

### Required:

@include 'packer-plugin-sdk/multistep/commonsteps/ISOConfig-required.mdx'

### Optional:

@include 'packer-plugin-sdk/multistep/commonsteps/ISOConfig-not-required.mdx'

## Http directory configuration

@include 'packer-plugin-sdk/multistep/commonsteps/HTTPConfig.mdx'

### Optional:

@include 'packer-plugin-sdk/multistep/commonsteps/HTTPConfig-not-required.mdx'

## Floppy configuration

@include 'packer-plugin-sdk/multistep/commonsteps/FloppyConfig.mdx'

### Optional:

@include 'packer-plugin-sdk/multistep/commonsteps/FloppyConfig-not-required.mdx'

### CD configuration

@include 'packer-plugin-sdk/multistep/commonsteps/CDConfig.mdx'

#### Optional:

@include 'packer-plugin-sdk/multistep/commonsteps/CDConfig-not-required.mdx'

## Shutdown configuration

### Optional:

@include 'packer-plugin-sdk/shutdowncommand/ShutdownConfig-not-required.mdx'

## Communicator configuration

### Optional common fields:

@include 'packer-plugin-sdk/communicator/Config-not-required.mdx'

@include 'builder/qemu/CommConfig-not-required.mdx'

### Optional SSH fields:

@include 'packer-plugin-sdk/communicator/SSH-not-required.mdx'

@include 'packer-plugin-sdk/communicator/SSH-Private-Key-File-not-required.mdx'

### Optional WinRM fields:

@include 'packer-plugin-sdk/communicator/WinRM-not-required.mdx'

## Boot Configuration

@include 'packer-plugin-sdk/bootcommand/VNCConfig.mdx'

@include 'packer-plugin-sdk/bootcommand/BootConfig.mdx'

### Optional:

@include 'packer-plugin-sdk/bootcommand/VNCConfig-not-required.mdx'

@include 'packer-plugin-sdk/bootcommand/BootConfig-not-required.mdx'

### Communicator Configuration

#### Optional:

@include 'packer-plugin-sdk/communicator/Config-not-required.mdx'

### Troubleshooting

#### Invalid Keymaps

Some users have experienced errors complaining about invalid keymaps. This
seems to be related to having a `common` directory or file in the directory
they've run Packer in, like the packer source directory. This appears to be an
upstream bug with qemu, and the best solution for now is to remove the
file/directory or run in another directory.

Some users have reported issues with incorrect keymaps using qemu version 2.11.
This is a bug with qemu, and the solution is to upgrade, or downgrade to 2.10.1
or earlier.

#### Corrupted image after Packer calls qemu-img convert on OSX

Due to an upstream bug with `qemu-img convert` on OSX, sometimes the qemu-img
convert call will create a corrupted image. If this is an issue for you, make
sure that the the output format (provided using the option `format`) matches
the input file's format and file extension, and Packer will
perform a simple copy operation instead. You will also want to set
`"skip_compaction": true,` and `"disk_compression": false` to skip a final
image conversion at the end of the build. See
https://bugs.launchpad.net/qemu/+bug/1776920 for more details.