guest_environments
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
meta
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
See also: Common Body Attributes
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
See also: Common Body Attributes
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:
The guest machine is allocated, installed and left in a running state.
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";
}