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NAME

Sys::Virt - Represent and manage a libvirt hypervisor connection

SYNOPSIS

  my $vmm = Sys::Virt->new(address => $addr);

  my @domains = $vmm->list_domains();

  foreach my $dom (@domains) {
    print "Domain ", $dom->get_id, " ", $dom->get_name, "\n";
  }

DESCRIPTION

The Sys::Virt module provides a Perl XS binding to the libvirt virtual machine management APIs. This allows machines running within arbitrary virtualization containers to be managed with a consistent API.

ERROR HANDLING

Any operations in the Sys::Virt API which have failure scenarios will result in an instance of the Sys::Virt::Error module being thrown. To catch these errors, simply wrap the method in an eval block. For details of the information contained in the error objects, consult the Sys::Virt::Error manual page.

METHODS

my $vmm = Sys::Virt->new(uri => $uri, readonly => $ro);

Attach to the virtual machine monitor with the address of address. The uri parameter may be omitted, in which case the default connection made will be to the local Xen hypervisor. Some example URIs include:

xen:///

Xen on the local machine

test:///default

Dummy "in memory" driver for test suites

qemu:///system

System-wide driver for QEMU / KVM virtualization

qemu:///session

Per-user driver for QEMU virtualization

qemu+tls://somehost/system

System-wide QEMU driver on somehost using TLS security

xen+tcp://somehost/

Xen driver on somehost using TCP / SASL security

For further details consult http://libvirt.org/uri.html

If the optional readonly parameter is supplied, then an unprivileged connection to the VMM will be attempted. If it is not supplied, then it defaults to making a fully privileged connection to the VMM. If the calling application is not running as root, it may be neccessary to provide authentication callbacks.

my $dom = $vmm->create_domain($xml);

Create a new domain based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::Domain class. This method is not available with unprivileged connections to the VMM.

my $dom = $vmm->define_domain($xml);

Defines, but does not start, a new domain based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::Domain class. This method is not available with unprivileged connections to the VMM. The define can be later started by calling the create method on the returned Sys::Virt::Domain object.

my $dom = $vmm->create_network($xml);

Create a new network based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::Network class. This method is not available with unprivileged connections to the VMM.

my $dom = $vmm->define_network($xml);

Defines, but does not start, a new network based on the XML description passed into the $xml parameter. The returned object is an instance of the Sys::Virt::Network class. This method is not available with unprivileged connections to the VMM. The define can be later started by calling the create method on the returned Sys::Virt::Network object.

my @doms = $vmm->list_domains()

Return a list of all domains currently known to the VMM. The elements in the returned list are instances of the Sys::Virt::Domain class.

my $nids = $vmm->num_of_domains()

Return the number of running domains known to the VMM. This can be used as the maxids parameter to list_domain_ids.

my @domIDs = $vmm->list_domain_ids($maxids)

Return a list of all domain IDs currently known to the VMM. The IDs can be used with the get_domain_by_id method.

my @doms = $vmm->list_defined_domains()

Return a list of all domains defined, but not currently running, on the VMM. The elements in the returned list are instances of the Sys::Virt::Domain class.

my $nids = $vmm->num_of_defined_domains()

Return the number of running domains known to the VMM. This can be used as the maxnames parameter to list_defined_domain_names.

my @doms = $vmm->list_defined_domain_names($maxnames)

Return a list of names of all domains defined, but not currently running, on the VMM. The names can be used with the get_domain_by_name method.

my $dom = $vmm->get_domain_by_name($name)

Return the domain with a name of $name. The returned object is an instance of the Sys::Virt::Domain class.

my @nets = $vmm->list_networks()

Return a list of all networks currently known to the VMM. The elements in the returned list are instances of the Sys::Virt::Network class.

my $nnames = $vmm->num_of_networks()

Return the number of running networks known to the VMM. This can be used as the maxids parameter to list_network_ids.

my @netNames = $vmm->list_network_names($maxnames)

Return a list of all network IDs currently known to the VMM. The IDs can be used with the get_network_by_id method.

my @nets = $vmm->list_defined_networks()

Return a list of all networks defined, but not currently running, on the VMM. The elements in the returned list are instances of the Sys::Virt::Network class.

my $nids = $vmm->num_of_defined_networks()

Return the number of running networks known to the VMM. This can be used as the maxnames parameter to list_defined_network_names.

my @doms = $vmm->list_defined_network_names($maxnames)

Return a list of names of all networks defined, but not currently running, on the VMM. The names can be used with the get_network_by_name method.

my $dom = $vmm->get_domain_by_name($name)

Return the domain with a name of $name. The returned object is an instance of the Sys::Virt::Domain class.

my $dom = $vmm->get_domain_by_id($id)

Return the domain with a local id of $id. The returned object is an instance of the Sys::Virt::Domain class.

my $dom = $vmm->get_domain_by_uuid($uuid)

Return the domain with a globally unique id of $uuid. The returned object is an instance of the Sys::Virt::Domain class.

my $dom = $vmm->get_network_by_name($name)

Return the network with a name of $name. The returned object is an instance of the Sys::Virt::Network class.

my $dom = $vmm->get_network_by_uuid($uuid)

Return the network with a globally unique id of $uuid. The returned object is an instance of the Sys::Virt::Network class.

$vmm->restore_domain($savefile)

Recreate a domain from the saved state file given in the $savefile parameter.

$vmm->get_max_vcpus($domtype)

Return the maximum number of vcpus that can be configured for a domain of type $domtype

$vmm->get_hostname()

Return the name of the host with which this connection is associated.

my $type = $vmm->get_type()

Return the type of virtualization backend accessed by this VMM object. Currently the only supported type is Xen.

my $ver = $vmm->get_version()

Return the complete version number as a string encoded in the formula (major * 1000000) + (minor * 1000) + micro.

my $ver = $vmm->get_major_version

Return the major version number of the libvirt library.

my $ver = $vmm->get_minor_version

Return the minor version number of the libvirt library.

my $ver = $vmm->get_micro_version

Return the micro version number of the libvirt library.

my $info = $con->get_node_info()

Returns a hash reference summarising the capabilities of the host node. The elements of the hash are as follows:

memory

The amount of physical memory in the host

model

The model of the CPU, eg x86_64

cpus

The total number of logical CPUs

mhz

The peak MHZ of the CPU

nodes

The number of NUMA cells

sockets

The number of CPU sockets

cores

The number of cores per socket

threads

The number of threads per core

my $xml = $con->get_capabilities();

Returns an XML document describing the hypervisor capabilities

BUGS

Hopefully none, but the XS code needs to be audited to ensure it is not leaking memory.

AUTHORS

Daniel P. Berrange <berrange@redhat.com>

COPYRIGHT

Copyright (C) 2006 Red Hat Copyright (C) 2006-2007 Daniel P. Berrange

LICENSE

This program is free software; you can redistribute it and/or modify it under the terms of either the GNU General Public License as published by the Free Software Foundation (either version 2 of the License, or at your option any later version), or, the Artistic License, as specified in the Perl README file.

SEE ALSO

Sys::Virt::Domain, Sys::Virt::Network, Sys::Virt::Error, http://libvirt.org