start cloud-init documentation

gen-qm-cloud-init-opts.pl

@@ -0,0 +1,16 @@
+#!/usr/bin/perl
+
+use lib '.';
+use strict;
+use warnings;
+use PVE::JSONSchema;
+use PVE::RESTHandler;
+use PVE::QemuServer;
+
+my $prop = PVE::QemuServer::cloudinit_config_properties();
+
+my $data = PVE::RESTHandler::dump_properties($prop, 'asciidoc', 'config');
+
+$data =~ s/cloud-init: //g;
+
+print $data;

qm.adoc

@@ -537,6 +537,136 @@ process a great number of incoming connections, such as when the VM is running
 as a router, reverse proxy or a busy HTTP server doing long polling.
 
 
+[[qm_cloud_init]]
+Cloud-Init Support
+~~~~~~~~~~~~~~~~~~
+
+http://cloudinit.readthedocs.io[Cloud-Init] is the defacto
+multi-distribution package that handles early initialization of a
+virtual machine instance. Using Cloud-Init, one can configure network
+devices and ssh keys on the hypervisor side. When the VM starts the
+first time, the Cloud-Init software inside the VM applies those
+settings.
+
+Many Linux distributions provides ready-to-use Cloud-Init images,
+mostly designed for 'OpenStack'. Those images also works with
+{pve}. While it may be convenient to use such read-to-use images, we
+usually recommend to prepare those images by yourself. That way you know
+exactly what is installed, and you can easily customize the image for
+your needs.
+
+Once you created such image, it is best practice to convert it into a
+VM template. It is really fast to create linked clones of VM
+templates, so this is a very fast way to roll out new VM
+instances. You just need to configure the network (any maybe ssh keys)
+before you start the new VM.
+
+We recommend the use of SSH key-based authentication to login to VMs
+provisioned by Cloud-Init. It is also possible to set a password, but
+{pve} needs to store an encrypted version of that password inside the
+Cloud-Init data. So this is not as safe as using SSH key-based
+authentication.
+
+{pve} generates an ISO image to pass the Cloud-Init data to the VM. So
+all Cloud-Init VMs needs to have an assigned CDROM drive for that
+purpose. Also, many Cloud-Init Images assumes to have a serial
+console, so it is best to add a serial console and use that as display
+for those VMs.
+
+
+Prepare Cloud-Init Templates
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The first step is to prepare your VM. You can basically use any VM,
+and simply install the Cloud-Init packages inside the VM you want to
+prepare. On Debian/Ubuntu based systems this is as simple as:
+
+----
+apt-get install cloud-init
+----
+
+Many distributions provides ready-to-use Cloud-Init images (provided
+as `.qcow2` files), so as alternative you can simply download and
+import such image. For the following example, we will use the cloud
+images provided by Ubuntu at https://cloud-images.ubuntu.com.
+
+----
+# download the image
+wget https://cloud-images.ubuntu.com/bionic/current/bionic-server-cloudimg-amd64.img
+
+# create a new VM
+qm create 9000 --memory 2048 --net0 virtio,bridge=vmbr0
+
+# import the downloaded disk to local-lvm storage
+qm importdisk 9000 bionic-server-cloudimg-amd64.img local-lvm
+
+# finally attach the new disk to the VM as scsi drive
+qm set 9000 --scsihw virtio-scsi-pci --scsi0 local-lvm:vm-9000-disk-1
+----
+
+NOTE: Ubuntu Cloud-Init images requires the `virtio-scsi-pci`
+controller type for SCSI drives.
+
+
+The next step is to configure a CDROM drive, used to pass the
+Cloud-Init data to the VM.
+
+----
+qm set 9000 --ide2 local-lvm:cloudinit
+----
+
+We want to boot directly from the Cloud-Init image, so we set the
+`bootdisk` parameter to `scsi0` and restrict BIOS to boot from disk
+only. This simply speeds up booting, because VM BIOS skips testing for
+a bootable CDROM.
+
+----
+qm set 9000 --boot c --bootdisk scsi0
+----
+
+We also want to configure a serial console and use that as display. Many Cloud-Init images rely on that, because it is an requirement for OpenStack images. 
+
+----
+qm set 9000 --serial0 socket --vga serial0
+----
+
+Finally, it is usually a good idea to transform such VM into a template. You can create linked clones with them, so deployment from VM templates is much faster than creating a full clone (copy).
+
+----
+qm template 9000
+----
+
+
+Deploy Cloud-Init Templates
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+You can easily deploy such template by cloning:
+
+----
+qm clone 9000 123 --name ubuntu2
+----
+
+Then configure the SSH public key used for authentication, and the IP setup
+
+----
+qm set 123 --sshkey ~/.ssh/id_rsa.pub
+qm set 123 --ipconfig0 ip=10.0.10.123/24,gw=10.0.10.1
+----
+
+You can configure all Cloud-Init options using a single command. I
+just split above example to separate commands to reduce the line
+length. Also make sure you adopt the IP setup for your environment.
+
+
+Cloud-Init specific Options
+^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+
+
+include::qm-cloud-init-opts.adoc[]
+
+
+
 [[qm_usb_passthrough]]
 USB Passthrough
 ~~~~~~~~~~~~~~~