Table of Contents

guest_environments

Table of Contents

Guest environment promises describe enclosed computing environments that can host physical and virtual machines, Solaris zones, grids, clouds or other enclosures, including embedded systems. CFEngine will support the convergent maintenance of such inner environments in a fixed location, with interfaces to an external environment.

CFEngine currently seeks to add convergence properties to existing interfaces for automatic self-healing of guest environments. The current implementation integrates with libvirt, supporting host virtualization for Xen, KVM, VMWare, etc. Thus CFEngine, running on a virtual host, can maintain the state and deployment of virtual guest machines defined within the libvirt framework. Guest environment promises are not meant to manage what goes on within the virtual guests. For that purpose you should run CFEngine directly on the virtual machine, as if it were any other machine.

 site1::

  "unique_name1"

       environment_resources => myresources("2GB","512MB"),
       environment_interface => mymachine("hostname"),
            environment_type => "xen",
            environment_state => "running",
            environment_host => "atlas";

  "unique_name2"

            environment_type => "xen_net",
           environment_state => "create",
            environment_host => "atlas";

CFEngine currently provides a convergent interface to libvirt.

Attributes

Common Attributes

Common attributes are available to all promise types. Full details for common attributes can be found in the Common Attributes section of the Promise Types and Attributes page. The common attributes are as follows:

action

classes

comment

depends_on

handle

ifvarclass

environment_host

Description: environment_host is a class indicating which physical node will execute this guest machine

The promise will only apply to the machine with this class set. Thus, CFEngine must be running locally on the hypervisor for the promise to take effect.

Type: string

Allowed input range: [a-zA-Z0-9_]+

Example:

guest_environments:

 linux::

 "host1"
                 comment => "Keep this vm suspended",
   environment_resources => myresources,
        environment_type => "kvm",
       environment_state => "suspended",
        environment_host => "ubuntu";

This attribute is required.

History: this feature was introduced in Nova 2.0.0 (2010), Community 3.3.0 (2012)

environment_interface

Type: body environment_interface

Common Body Attributes

Common body attributes are available to all body types. Full details for common body attributes can be found in the Common Body Attributes section of the Promise Types and Attributes page. The common attributes are as follows:

inherit_from

env_addresses

Description: env_addresses is the IP addresses of the environment's network interfaces

The IP addresses of the virtual machine can be overridden here at run time.

Type: slist

Allowed input range: (arbitrary string)

Example:

     body environment_interface vnet(primary)
     {
     env_name      => "$(this.promiser)";
     env_addresses => { "$(primary)" };

     host1::

       env_network => "default_vnet1";

     host2::

       env_network => "default_vnet2";

     }

env_name

Description: env_name is the hostname of the virtual environment.

The 'hostname' of a virtual guest may or may not be the same as the identifier used as 'promiser' by the virtualization manager.

Type: string

Allowed input range: (arbitrary string)

Example:

     body environment_interface vnet(primary)
     {
     env_name      => "$(this.promiser)";
     env_addresses => { "$(primary)" };

     host1::
       env_network => "default_vnet1";

     host2::
       env_network => "default_vnet2";
     }

env_network

Description: The hostname of the virtual network

Type: string

Allowed input range: (arbitrary string)

Example:

    body environment_interface vnet(primary)
    {
    env_name      => "$(this.promiser)";
    env_addresses => { "$(primary)" };

    host1::
      env_network => "default_vnet1";

    host2::
      env_network => "default_vnet2";
    }

environment_resources

Type: body environment_resources

Common Body Attributes

inherit_from

env_cpus

Description: env_cpus represents the number of virtual CPUs in the environment.

The maximum number of cores or processors in the physical environment will set a natural limit on this value.

Type: int

Allowed input range: 0,99999999999

Example:

     body environment_resources my_environment
     {
     env_cpus => "2";
     env_memory => "512"; # in KB
     env_disk => "1024";  # in MB
     }

Notes: This attribute conflicts with env_spec.

env_memory

Description: env_memory represents the amount of primary storage (RAM) in the virtual environment (in KB).

The maximum amount of memory in the physical environment will set a natural limit on this value.

Type: int

Allowed input range: 0,99999999999

Example:

     body environment_resources my_environment
     {
     env_cpus => "2";
     env_memory => "512"; # in KB
     env_disk => "1024";  # in MB
     }

Notes: This attribute conflicts with env_spec.

env_disk

Description: env_disk represents the amount of secondary storage (DISK) in the virtual environment (in KB).

This parameter is currently unsupported, for future extension.

Type: int

Allowed input range: 0,99999999999

Example:

     body environment_resources my_environment
     {
     env_cpus => "2";
     env_memory => "512"; # in KB
     env_disk => "1024";  # in MB
     }

Notes: This parameter is currently unsupported, for future extension.

This attribute conflicts with env_spec.

env_baseline

Description: The env_baseline string represents a path to an image with which to baseline the virtual environment.

Type: string

Allowed input range: "?(/.*)

Example:

     env_baseline => "/path/to/image";

Notes: This function is for future development.

env_spec

Description: A env_spec string contains a technology specific set of promises for the virtual instance.

This is the preferred way to specify the resources of an environment on creation; in other words, when environment_state is create.

Type: string

Allowed input range: .*

Example:

     body environment_resources virt_xml(host)
     {
     env_spec =>

     "<domain type='xen'>
       <name>$(host)/name>
       <os>
         <type>linux/type>
         <kernel>/var/lib/xen/install/vmlinuz-ubuntu10.4-x86_64/kernel>
         <initrd>/var/lib/xen/install/initrd-vmlinuz-ubuntu10.4-x86_64/initrd>
         <cmdline> kickstart=http://example.com/myguest.ks /cmdline>
       </os>
       <memory>131072/memory>
       <vcpu>1/vcpu>
       <devices>
         <disk type='file'>
           <source file='/var/lib/xen/images/$(host).img'/>
           <target dev='sda1'/>
         </disk>
         <interface type='bridge'>
           <source bridge='xenbr0'/>
           <mac address='aa:00:00:00:00:11'/>
           <script path='/etc/xen/scripts/vif-bridge'/>
         </interface>
         <graphics type='vnc' port='-1'/>
         <console tty='/dev/pts/5'/>
       </devices>
     </domain>
     ";
     }

Notes:

This attribute conflicts with env_cpus, env_memory and env_disk.

History: Was introduced in version 3.1.0b1,Nova 2.0.0b1 (2010)

environment_state

Description: The environment_state defines the desired dynamic state of the specified environment.

Type: (menu option)

Allowed input range:

create

The guest machine is allocated, installed and left in a running state.

delete

The guest machine is shut down and deallocated, but no files are removed.

running

The guest machine is in a running state, if it previously exists.

suspended

The guest exists in a suspended state or a shutdown state. If the guest is running, it is suspended; otherwise it is ignored.

down

The guest machine is shut down, but not deallocated.

Example:

guest_environments:

 linux::

 "bishwa-kvm1"
                 comment => "Keep this vm suspended",
   environment_resources => myresources,
        environment_type => "kvm",
       environment_state => "suspended",
        environment_host => "ubuntu";

environment_type

Description: environment_type defines the virtual environment type.

The currently supported types are those supported by libvirt. More will be added in the future.

Type: (menu option)

Allowed input range:

    xen
    kvm
    esx
    vbox
    test
    xen_net
    kvm_net
    esx_net
    test_net
    zone
    ec2
    eucalyptus

Example:

bundle agent my_vm_cloud
{
guest_environments:

 scope::

   "vguest1"

       environment_resources => my_environment_template,
       environment_interface => vnet("eth0,192.168.1.100/24"),
       environment_type      => "test",
       environment_state     => "create",
       environment_host      => "atlas";

   "vguest2"

       environment_resources => my_environment_template,
       environment_interface => vnet("eth0,192.168.1.101/24"),
       environment_type      => "test",
       environment_state     => "delete",
       environment_host      => "atlas";
}

guest_environments

Attributes

Common Attributes

action

classes

comment

depends_on

handle

ifvarclass

meta

environment_host

environment_interface

Common Body Attributes

inherit_from

meta

env_addresses

env_name

env_network

environment_resources

Common Body Attributes

inherit_from

meta

env_cpus

env_memory

env_disk

env_baseline

env_spec

environment_state

environment_type