VM::EC2::Instance::Metadata - Object describing the metadata of a running
# For use within a running EC2 instance only!
my $meta = VM::EC2::Instance::Metadata->new;
my $meta = VM::EC2->instance_metadata;
my $meta = $instance->metadata;
# image information
$image_id = $meta->imageId;
$index = $meta->imageLaunchIndex;
$path = $meta->amiManifestPath;
$location = $meta->imageLocation; # same as previous
@ancestors = $meta->ancestorAmiIds;
@ancestors = $meta->imageAncestorIds; # same as previous
@codes = $meta->productCodes;
# launch and runtime information
$inst_id = $meta->instanceId;
$kern_id = $meta->kernelId;
$rd_id = $meta->ramdiskId;
$res_id = $meta->reservationId;
$type = $meta->instanceType;
$zone = $meta->availabilityZone;
$userdata = $meta->userData;
@groups = $meta->securityGroups;
@keys = $meta->publicKeys;
$block_dev = $meta->blockDeviceMapping; # a hashref
# Network information
$priv_name = $meta->localHostname;
$priv_name = $meta->privateDnsName; # same as previous
$priv_ip = $meta->localIpv4;
$priv_ip = $meta->privateIpAddress;
$mac = $meta->mac;
$pub_name = $meta->publicHostname;
$pub_name = $meta->dnsName; # same as previous
$pub_ip = $meta->publicIpv4;
$pub_ip = $meta->ipAddress;
$interfaces= $meta->interfaces; # a hashref
# IAM information
$iam_info = $metadata->iam_info; # a hashref
$iam_role = $metadata->iam_role; # name of the role
$credentials= $metadata->iam_credentials; # VM::EC2::Security::Credentials object
# Undocumented fields
$action = $meta->instanceAction;
$profile = $meta->profile;
This is an interface to the metadata that is provided to a running instance via
the http://169.254.169.254/latest URL, as described in
Each metadata object caches its values, so there is no overhead in calling a
method repeatedly. Methods return scalar values, lists and hashrefs as
The methods from this class should only be called within the context of a
running EC2 instance. Attempts to call outside of this context will result in
long delays as the module attempts to connect to an invalid hostname.
You can create a new metadata object either using this class's new()
constructor, or by calling an VM::EC2 object's instance_metadata()
method, or by calling a VM::EC2::Instance object's metadata () method.
The following methods all return single-valued results:
- Image information:
imageId -- ID of AMI used to launch this instance
imageLaunchIndex -- This index's launch index. If four instances
were launched by one $image->run_instances()
call, they will be numbered from 0 to 3.
amiManifestPath -- S3 path to the image
imageLocation -- Same as amiManifestPath(), for consistency with
- Launch and runtime information:
instanceId -- ID of this instance
kernelId -- ID of this instance's kernel.
ramdiskId -- This instance's ramdisk ID
reservationId -- This instance's reservation ID
instanceType -- Machine type, e.g. "m1.small"
availabilityZone -- This instance's availability zone.
region -- This instance's region.
endpoint -- This instance's endpoint.
userData -- User data passed at launch time.
- Network information:
localHostname -- The instance hostname corresponding to its
internal EC2 IP address.
privateDnsName -- Same as localHostname(), for consistency with
localIpv4 -- The instance IP address on the internal EC2 network.
privateIpAddress -- Same as localIpv4(), for consistency with
mac -- This instance's MAC (ethernet) address.
publicHostname -- This instance's public hostname.
dnsName -- Same as publicHostname() for consistency with
publicIpv4 -- This instance's public IP address.
ipAddress -- Same as publicIpv4() for consistency with
- IAM information
- These routines return information about the instance's IAM role, if any.
These calls also provide a temporary security credentials for making EC2
calls, as described here:
Note that these routines require installation of the perl JSON module, and
will cause a fatal error if this module cannot be loaded.
iam_info -- Returns a hash containing the fields 'LastUpdated',
'InstanceProfileArn', and 'InstanceProfileId'. These
provide information about the instance's IAM role.
iam_role -- Returns the IAM role name for the currently running
iam_credentials -- Returns a VM::EC2::Security::Credentials object that can
be passed to VM::EC2->new(-security_token=>$credentials).
- Unknown information:
profile -- An undocumented field that contains the virtualization
type in the form "default-paravirtual".
instanceAction -- Undocumented metadata field named "instance-action"
The following methods all return lists.
- Image information
ancestorAmiIds -- List of AMIs from which the current one was derived
imageAncestorIds -- Same as ancestorAmiIds() but easier to read.
productCodes -- List of product codes applying to the image from which
this instance was launched.
- Launch and runtime information
securityGroups -- List of security groups to which this instance is assigned.
For non-VPC instances, this will be the security group
name. For VPC instances, this will be the security group ID.
publicKeys -- List of public key pair names attached to this instance.
The following methods return a hashref for representing complex data structures:
- $devices = $meta->blockDeviceMapping
- This returns a hashref in which the keys are the names of instance block
devices, such as "/dev/sda1", and the values are the EC2 virtual
machine names. For example:
'/dev/sda1' => 'root'
'/dev/sda2' => 'ephemeral0'
'/dev/sdg' => 'ebs1'
'/dev/sdh' => 'ebs9'
'/dev/sdi' => 'ebs10'
'sda3' => 'swap'
For reasons that are not entirely clear, the swap device is reported as
"sda3" rather than as "/dev/sda3".
- $interfaces = $meta->interfaces
- Returns a mapping of all virtual ethernet devices owned by this instance.
This is primarily useful for VPC instances, which can have more than one
device. The hash keys are the MAC addresses of each ethernet device, and
the values are hashes that have the following keys:
localIpv4s (an array ref)
publicIpv4s (an array ref)
securityGroupIds (an array ref)
'12:31:38:01:b8:97' => HASH(0x9eaa090)
'localHostname' => 'domU-12-31-38-01-B8-97.compute-1.internal'
'localIpv4s' => ARRAY(0x9b4f8a8)
'mac' => '12:31:38:01:b8:97'
'publicIpv4s' => ARRAY(0x9ea9e40)
'securityGroupIds' => ARRAY(0x9eaa490)
'subnetId' => undef
'subnetIpv4CidrBlock' => undef
'vpcId' => undef
'vpcIpv4CidrBlock' => undef
VM::EC2 VM::EC2::Generic VM::EC2::BlockDevice VM::EC2::State::Reason
VM::EC2::State VM::EC2::Instance VM::EC2::Tag
Lincoln Stein <firstname.lastname@example.org>.
Copyright (c) 2011 Ontario Institute for Cancer Research
This package and its accompanying libraries is free software; you can
redistribute it and/or modify it under the terms of the GPL (either version 1,
or at your option, any later version) or the Artistic License 2.0. Refer to
LICENSE for the full license text. In addition, please see DISCLAIMER.txt for
disclaimers of warranty.