Ansible role vm_libvirt_cloudinit

This role allow to deploy a vm on a target host while providing an interface to customize it using cloud-init.

Examples

# Deploy `myvm` as vm on `virtualizer` using ubuntu cloud image as a base.
-   hosts: myvm
    gather_facts: no
    roles:
    -   role: vm_libvirt_cloudinit
        vm_hoster: virtualizer
        vm_drives:
        -   type: file
            source: https://cloud-images.ubuntu.com/xenial/current/xenial-server-cloudimg-amd64-disk1.img

# Deploy `myvm` as vm on `virtualizer` using a local copy of ubuntu 
# 16.04 image as a base.
# Manage a logical volume to use as backing device.
# Run a script on boot
-   hosts: myvm
    roles:
    -   role: vm_libvirt_cloudinit
        vm_hoster: virtualizer
        vm_drives:
        -   type: block
            source: /opt/xenial-server-cloudimg-amd64-disk1.img
            path: /dev/cinder-volumes/myvm_root
            managed: yes
            size_gb: 3
        vm_userdata: |
            #!/bin/bash
            # WARN: this is not secure
            echo 'root:password' | chpasswd
            
# Deploy `myvm` as vm on `virtualizer` using centos cloud image.
# Attach a first network interface as a macvlan sub-interface to `eth0`
# and a second one to a openvswitch switch named br-ex, trunking tags
# 30-40.
# Configure the vm via cloud-init
-   hosts: myvm
    roles:
    -   role: vm_libvirt_cloudinit
        vm_hoster: virtualizer
        vm_drives:
        -   type: block
            source: /opt/centos7-base.qcow2
            path: /dev/cinder-volumes/myvm_root
            managed: yes
            size_gb: 10
        vm_networks:
        -   type: direct
            parent: eth0
            address: 10.20.0.2/24
            gateway: 10.20.0.1
        -   type: openvswitch
            parent: br-ex
            trunk: "{{range(30, 41)|list}}"
        vm_userdata:
            users:
            -   name: username
                gecos: User Name
                sudo: ALL=(ALL) NOPASSWD:ALL
                groups: users, admin
                lock_passwd: true
                shell: /bin/bash
                ssh_authorized_keys:
                -   ssh-rsa AAA[...]
            write_files:
            -   path: /etc/hosts
                content: |
                    127.0.0.1 localhost
                    10.20.0.2 test
                owner: root:root
                permissions: '0644'

Network Configuration

The roles variable vm_networks is a list of dictionaries used to define the network interfaces which will be attached to the vm. Each element must contain the key type, set to bridge, direct or openvswitch.

The network interface will be attached to: A linuxbridge identified by the parent key if network.type=="bridge". A macvlan sub-interface of the network device identified by the parent key if network.type=="direct". An openvswitch switch identified by the parent key if network.type=="openvswitch"

If attaching to an openvswitch switch these keys can also be used:

• trunk: list of tags to trunk to the openvswitch port
• access: tag to apply to the openvswitch port

For any configuration the element can contain these keys:

• mac: statically assign a mac address to the interface
• address: network address, expressed as address/netmask (es. 192.168.0.1/24)
• gateway: gateway ip for the interface

Using the values in this list the role will generate the <interface> sections of the libvirt domain and the cloud-init network-config data.

Storage Configuration

The roles variable vm_drives is a list of dictionaries used to define the drives which will be attached to the vm. Each element must contain the key type, set to file or block.

If drive.managed==True (the default) the role will need a key size_gb to be set, and it will create an image for the drive:

• if type=='file'
  • if path is not set it will default to {{vm_dir}}/drive_{{idx}}.img
  • if format is not set it will default to qcow2
• if type=='block'
  • path is required with format /dev/$vg/$lv, the corresponding logical volume will be created
  • if format is not set it will default to raw

If drive.source is set the drive will be populated with the referenced source image.

Role variables

The role uses the following variables, here listed with their default values:

vm_hoster:

This variable is mandatory. It must be set to the ansible_hostname of the system on which this role will spawn the vm.

vm_hostname: "{{inventory_hostname}}"

The hostname of the vm.

vm_autostart: true
vm_start: true
vm_delete: false
vm_rebuild: false

These variables controls the lifecycle of the vm.

vm_cpus: 2
vm_memory_mb: 512

Resources allocated to the vm

vm_dir: "/opt/vms/{{vm_hostname}}"
vm_cloudinit_iso: "{{vm_dir}}/nocloud.iso"

In vm_dir the role will place:

• user-data, meta-data, network-data and nocloud.iso: files used to configure the vm via cloud-init
• domain.xml: a dump of the vm libvirt domain definition
• drive_N.img: the vm drives created by this module

vm_drives:
-   type: file
    format: qcow2
    source: https://cloud-images.ubuntu.com/xenial/current/xenial-server-cloudimg-amd64-disk1.img
    size_gb: 5

List of drives which will be attached to the vm. See Strorage Configuration

vm_networks: []

List of network interfaces which will be attached to the vm. See Network Configuration

vm_nameservers:
-   8.8.8.8

DNS servers configured on the vm.

vm_userdata: {}

Cloud-init's user-data. Can be give an as inline YAML or as a string. (see examples)

vm_vnc_address: 127.0.0.1
vm_vnc_port: 0

Address and port on which the libvirt domain vnc server will bind. If vm_vnc_port==0 no vnc server will be attached to the vm. If vm_vnc_port==-1 a port will be autoallocated by libvirt.

vm_wait_for_tcp22: "{{vm_start}}"
vm_wait_for_tcp22_delegate: true

If vm_wait_for_tcp22==True the role will wait until vm_hoster will be able to reach tcp22 on the first address defined on vm_networks. If vm_wait_for_tcp22_delegate==False this test will be performed from the deployment host.

---

vm_allow_passthrough: false

If true the libvirt domain cpu mode will be set to host-passthrough, allowing the definition on nested vms. If false the cpu model will follow the defaults for the vm_hoster libvirt daemon.

vm_do_bootstrap: true

If true the role will manage the vm_cloudinit_iso, vm_drives creation, otherwise only the domain will be defined.

vm_domain_type: kvm

The type attribute of the libvirt <domain>.

vm_cloudinit_iso: "{{vm_dir}}/nocloud.iso"

Path where the NoCloud datasource for cloud-init will be created

vm_emulator_path: "/usr/libexec/qemu-kvm"

Path to the qemu-kvm executable on vm_hoster

vm_identify_interfaces_by_parent: false

If true the role will match libvirt<->cloudinit interfaces mapping by parent, the default is to match by hwaddr. This option is here only as a retrocompatibility workaround, and should not be used.

vm_network_config_version: "1"

Version of the cloud-init network-config format to use.
Support for version "2" is not working, so this option should not be used.