VM::EC2::Instance::Metadata - Object describing the metadata of a running instance
# For use within a running EC2 instance only! use VM::EC2::Instance::Metadata; my $meta = VM::EC2::Instance::Metadata->new; # alternatively... 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 http://docs.amazonwebservices.com/AWSEC2/latest/UserGuide/index.html?instancedata-data-categories.html.
Each metadata object caches its values, so there is no overhead in calling a method repeatedly. Methods return scalar values, lists and hashrefs as appropriate.
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:
imageId -- ID of AMI used to launch this instance imageLaunchIndex -- This index's launch index. If four instances were launched by one $image->run_instances() call, they will be numbered from 0 to 3. amiManifestPath -- S3 path to the image imageLocation -- Same as amiManifestPath(), for consistency with VM::EC2::Image
instanceId -- ID of this instance kernelId -- ID of this instance's kernel. ramdiskId -- This instance's ramdisk ID reservationId -- This instance's reservation ID instanceType -- Machine type, e.g. "m1.small" availabilityZone -- This instance's availability zone. region -- This instance's region. endpoint -- This instance's endpoint. userData -- User data passed at launch time.
localHostname -- The instance hostname corresponding to its internal EC2 IP address. privateDnsName -- Same as localHostname(), for consistency with VM::EC2::Instance localIpv4 -- The instance IP address on the internal EC2 network. privateIpAddress -- Same as localIpv4(), for consistency with VM::EC2::Instance. mac -- This instance's MAC (ethernet) address. publicHostname -- This instance's public hostname. dnsName -- Same as publicHostname() for consistency with VM::EC2::Instance. publicIpv4 -- This instance's public IP address. ipAddress -- Same as publicIpv4() for consistency with VM::EC2::Instance.
These routines return information about the instance's IAM role, if any. These calls also provide a temporary security credentials for making EC2 calls, as described here: http://docs.amazonwebservices.com/AWSEC2/latest/UserGuide/UsingIAM.html.
Note that these routines require installation of the perl JSON module, and will cause a fatal error if this module cannot be loaded.
iam_info -- Returns a hash containing the fields 'LastUpdated', 'InstanceProfileArn', and 'InstanceProfileId'. These provide information about the instance's IAM role. iam_role -- Returns the IAM role name for the currently running instance. iam_credentials -- Returns a VM::EC2::Security::Credentials object that can be passed to VM::EC2->new(-security_token=>$credentials).
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.
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.
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:
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:
x $meta->blockDeviceMapping 0 HASH(0x9b4f2f8) '/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".
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:
mac localHostname localIpv4s (an array ref) publicIpv4s (an array ref) securityGroupIds (an array ref) subnetId subnetIpv4CidrBlock vpcId vpcIpv4CidrBlock
D x $meta->interfaces 0 HASH(0x9b4f518) '12:31:38:01:b8:97' => HASH(0x9eaa090) 'localHostname' => 'domU-12-31-38-01-B8-97.compute-1.internal' 'localIpv4s' => ARRAY(0x9b4f8a8) 0 '10.253.191.101' 'mac' => '12:31:38:01:b8:97' 'publicIpv4s' => ARRAY(0x9ea9e40) 0 '126.96.36.199' 'securityGroupIds' => ARRAY(0x9eaa490) empty array 'subnetId' => undef 'subnetIpv4CidrBlock' => undef 'vpcId' => undef 'vpcIpv4CidrBlock' => undef
Lincoln Stein <email@example.com>.
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.