8 https://cloudinit.readthedocs.io[Cloud-Init] is the de facto
9 multi-distribution package that handles early initialization of a
10 virtual machine instance. Using Cloud-Init, configuration of network
11 devices and ssh keys on the hypervisor side is possible. When the VM
12 starts for the first time, the Cloud-Init software inside the VM will
15 Many Linux distributions provide ready-to-use Cloud-Init images, mostly
16 designed for 'OpenStack'. These images will also work with {pve}. While
17 it may seem convenient to get such ready-to-use images, we usually
18 recommended to prepare the images by yourself. The advantage is that you
19 will know exactly what you have installed, and this helps you later to
20 easily customize the image for your needs.
22 Once you have created such a Cloud-Init image we recommend to convert it
23 into a VM template. From a VM template you can quickly create linked
24 clones, so this is a fast method to roll out new VM instances. You just
25 need to configure the network (and maybe the ssh keys) before you start
28 We recommend using SSH key-based authentication to login to the VMs
29 provisioned by Cloud-Init. It is also possible to set a password, but
30 this is not as safe as using SSH key-based authentication because {pve}
31 needs to store an encrypted version of that password inside the
34 {pve} generates an ISO image to pass the Cloud-Init data to the VM. For
35 that purpose, all Cloud-Init VMs need to have an assigned CD-ROM drive.
36 Usually, a serial console should be added and used as a display. Many Cloud-Init
37 images rely on this, it is a requirement for OpenStack. However, other images
38 might have problems with this configuration. Switch back to the default display
39 configuration if using a serial console doesn't work.
42 Preparing Cloud-Init Templates
43 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
45 The first step is to prepare your VM. Basically you can use any VM.
46 Simply install the Cloud-Init packages inside the VM that you want to
47 prepare. On Debian/Ubuntu based systems this is as simple as:
50 apt-get install cloud-init
53 WARNING: This command is *not* intended to be executed on the {pve} host, but
56 Already many distributions provide ready-to-use Cloud-Init images (provided
57 as `.qcow2` files), so alternatively you can simply download and
58 import such images. For the following example, we will use the cloud
59 image provided by Ubuntu at https://cloud-images.ubuntu.com.
63 wget https://cloud-images.ubuntu.com/bionic/current/bionic-server-cloudimg-amd64.img
66 qm create 9000 --memory 2048 --net0 virtio,bridge=vmbr0
68 # import the downloaded disk to local-lvm storage
69 qm importdisk 9000 bionic-server-cloudimg-amd64.img local-lvm
71 # finally attach the new disk to the VM as scsi drive
72 qm set 9000 --scsihw virtio-scsi-pci --scsi0 local-lvm:vm-9000-disk-1
75 NOTE: Ubuntu Cloud-Init images require the `virtio-scsi-pci`
76 controller type for SCSI drives.
78 .Add Cloud-Init CD-ROM drive
80 [thumbnail="screenshot/gui-cloudinit-hardware.png"]
82 The next step is to configure a CD-ROM drive, which will be used to pass
83 the Cloud-Init data to the VM.
86 qm set 9000 --ide2 local-lvm:cloudinit
89 To be able to boot directly from the Cloud-Init image, set the
90 `bootdisk` parameter to `scsi0`, and restrict BIOS to boot from disk
91 only. This will speed up booting, because VM BIOS skips the testing for
95 qm set 9000 --boot c --bootdisk scsi0
98 For many Cloud-Init images, it is required to configure a serial console and use
99 it as a display. If the configuration doesn't work for a given image however,
100 switch back to the default display instead.
103 qm set 9000 --serial0 socket --vga serial0
106 In a last step, it is helpful to convert the VM into a template. From
107 this template you can then quickly create linked clones.
108 The deployment from VM templates is much faster than creating a full
115 Deploying Cloud-Init Templates
116 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
118 [thumbnail="screenshot/gui-cloudinit-config.png"]
120 You can easily deploy such a template by cloning:
123 qm clone 9000 123 --name ubuntu2
126 Then configure the SSH public key used for authentication, and configure
130 qm set 123 --sshkey ~/.ssh/id_rsa.pub
131 qm set 123 --ipconfig0 ip=10.0.10.123/24,gw=10.0.10.1
134 You can also configure all the Cloud-Init options using a single command
135 only. We have simply split the above example to separate the
136 commands for reducing the line length. Also make sure to adopt the IP
137 setup for your specific environment.
140 Custom Cloud-Init Configuration
141 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
143 The Cloud-Init integration also allows custom config files to be used instead
144 of the automatically generated configs. This is done via the `cicustom`
145 option on the command line:
148 qm set 9000 --cicustom "user=<volume>,network=<volume>,meta=<volume>"
151 The custom config files have to be on a storage that supports snippets and have
152 to be available on all nodes the VM is going to be migrated to. Otherwise the
153 VM won't be able to start.
157 qm set 9000 --cicustom "user=local:snippets/userconfig.yaml"
160 There are three kinds of configs for Cloud-Init. The first one is the `user`
161 config as seen in the example above. The second is the `network` config and
162 the third the `meta` config. They can all be specified together or mixed
163 and matched however needed.
164 The automatically generated config will be used for any that don't have a
165 custom config file specified.
167 The generated config can be dumped to serve as a base for custom configs:
170 qm cloudinit dump 9000 user
173 The same command exists for `network` and `meta`.
176 Cloud-Init specific Options
177 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
179 include::qm-cloud-init-opts.adoc[]
187 * link:/wiki/Qemu/KVM_Virtual_Machines[Qemu/KVM Virtual Machines]