$ curl http://169.254.169.254/openstack
2012-08-10
2013-04-04
2013-10-17
latest

To list supported versions for the EC2-compatible metadata API, make a GET request to http://169.254.169.254:

$ curl http://169.254.169.254
1.0
2007-01-19
2007-03-01
2007-08-29
2007-10-10
2007-12-15
2008-02-01
2008-09-01
2009-04-04
latest

If you write a consumer for one of these APIs, always attempt to access the most recent API version supported by your consumer first, then fall back to an earlier version if the most recent one is not available.

Metadata from the OpenStack API is distributed in JSON format. To retrieve the metadata, make a GET request tohttp://169.254.169.254/openstack/2012-08-10/meta_data.json:

$ curl http://169.254.169.254/openstack/2012-08-10/meta_data.json

1 2 3 4 5 6 7 8 9 10 11 12 13 14

{ "uuid": " d 8 e 0 2 d 5 6 - 2 6 4 8 - 4 9 a 3 - b f 9 7 - 6 b e 8 f 1 2 0 4 f 3 8 " , "availability_zone": " n o v a " , "hostname": " t e s t . n o v a l o c a l " , "launch_index": 0 , "meta": { "priority": " l o w " , "role": " w e b s e r v e r " } , "public_keys": { "mykey": " s s h - r s a A A A A B 3 N z a C 1 y c 2 E A A A A D A Q A B A A A A g Q D Y V E p r v t Y J X V O B N 0 X N K V V R N C R X 6 B l n N b I + U S L G a i s 1 s U W P w t S g 7 z 9 K 9 v h b Y A P U Z c q 8 c / s 5 S 9 d g 5 v T H b s i y P C I D O K y e H b a 4 M U J q 8 O h 5 b 2 i 7 1 / 3 B I S p y x T B H / u Z D H d s l W 2 a + S r P D C e u M M o s s 9 N F h B d K t D k d G 9 z y i 0 i b m C P 6 y M d E X 8 Q = = G e n e r a t e d b y N o v a \ n " } , "name": " t e s t " }

Instances also retrieve user data (passed as the user_data parameter in the API call or by the --user_data flag in the nova boot command) through the metadata service, by making a GET request to http://169.254.169.254/openstack/2012-08-10/user_data:

$ curl http://169.254.169.254/openstack/2012-08-10/user_data
#!/bin/bash
echo 'Extra user data here'

The metadata service has an API that is compatible with version 2009-04-04 of the Amazon EC2 metadata service. This means that virtual machine images designed for EC2 will work properly with OpenStack.

The EC2 API exposes a separate URL for each metadata element. Retrieve a listing of these elements by making a GET query tohttp://169.254.169.254/2009-04-04/meta-data/:

$ curl http://169.254.169.254/2009-04-04/meta-data/
ami-id
ami-launch-index
ami-manifest-path
block-device-mapping/
hostname
instance-action
instance-id
instance-type
kernel-id
local-hostname
local-ipv4
placement/
public-hostname
public-ipv4
public-keys/
ramdisk-id
reservation-id
security-groups

$ curl http://169.254.169.254/2009-04-04/meta-data/block-device-mapping/
ami

$ curl http://169.254.169.254/2009-04-04/meta-data/placement/
availability-zone

$ curl http://169.254.169.254/2009-04-04/meta-data/public-keys/
0=mykey

Instances can retrieve the public SSH key (identified by keypair name when a user requests a new instance) by making a GET request to http://169.254.169.254/2009-04-04/meta-data/public-keys/0/openssh-key:

$ curl http://169.254.169.254/2009-04-04/meta-data/public-keys/0/openssh-key
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAAAgQDYVEprvtYJXVOBN0XNKVVRNCRX6BlnNbI+USLGais1sUWPwtSg7z9K9vhbYAPUZcq8c/s5S9dg5vTHbsiyPCIDOKyeHba4MUJq8Oh5b2i71/3BISpyxTBH/uZDHdslW2a+SrPDCeuMMoss9NFhBdKtDkdG9zyi0ibmCP6yMdEX8Q== Generated by Nova

Instances can retrieve user data by making a GET request to http://169.254.169.254/2009-04-04/user-data:

$ curl http://169.254.169.254/2009-04-04/user-data
#!/bin/bash
echo 'Extra user data here'

The metadata service is implemented byeither the nova-api serviceor the nova-api-metadata service. Note thatthe nova-api-metadata service is generally only used when running in multi-host mode, as it retrieves instance-specific metadata.If you are running the nova-api service, you must have metadata as one of the elements listed in the enabled_apis configuration option in /etc/nova/nova.conf. The default enabled_apis configuration setting includes the metadata service, so you should not need to modify it.

Hosts access the service at 169.254.169.254:80, and this is translated to metadata_host:metadata_port by an iptables rule established by the nova-network service. In multi-host mode, you can set metadata_host to 127.0.0.1.

For instances to reach the metadata service, the nova-network service must configure iptables to NAT port 80 of the 169.254.169.254 address to the IP address specified in metadata_host (this defaults to $my_ip, which is the IP address of the nova-network service) and port specified in metadata_port(which defaults to 8775) in /etc/nova/nova.conf.

	Note
	The metadata_host configuration option must be an IP address, not a host name.

The default Compute service settings assume that nova-network and nova-api are running on the same host. If this is not the case, in the/etc/nova/nova.conf file on the host running nova-network, set the metadata_host configuration option to the IP address of the host where nova-apiis running.

Table 4.2. Description of metadata configuration options

Configuration option = Default value	Description
[DEFAULT]
metadata_cache_expiration = 15	(IntOpt) Time in seconds to cache metadata; 0 to disable metadata caching entirely (not recommended). Increasingthis should improve response times of the metadata API when under heavy load. Higher values may increase memoryusage and result in longer times for host metadata changes to take effect.
metadata_host = $my_ip	(StrOpt) The IP address for the metadata API server
metadata_listen = 0.0.0.0	(StrOpt) The IP address on which the metadata API will listen.
metadata_listen_port = 8775	(IntOpt) The port on which the metadata API will listen.
metadata_manager = nova.api.manager.MetadataManager	(StrOpt) OpenStack metadata service manager
metadata_port = 8775	(IntOpt) The port for the metadata API port
metadata_workers = None	(IntOpt) Number of workers for metadata service. The default will be the number of CPUs available.
vendordata_driver =nova.api.metadata.vendordata_json.JsonFileVendorData	(StrOpt) Driver to use for vendor data
vendordata_jsonfile_path = None	(StrOpt) File to load JSON formatted vendor data from

获取Openstack的虚拟机相关信息

获取EC2的虚拟机相关信息

获取user-data

Havana新增接口

可能会遇到的问题：