CloudStack

Apache CloudStack expose user-data, meta-data, user password and account SSH key thru the Virtual-Router. The datasource obtains the VR address via dhcp lease information given to the instance. For more details on meta-data and user-data, refer the CloudStack Administrator Guide.

URLs to access user-data and meta-data from the Virtual Machine. data-server. is a well-known hostname provided by the CloudStack virtual router that points to the next UserData server (which is usually also the virtual router).

http://data-server./latest/user-data
http://data-server./latest/meta-data
http://data-server./latest/meta-data/{metadata type}

If data-server. cannot be resolved, cloud-init will try to obtain the virtual router’s address from the system’s DHCP leases. If that fails, it will use the system’s default gateway.

Configuration

The following configuration can be set for the datasource in system configuration (in /etc/cloud/cloud.cfg or /etc/cloud/cloud.cfg.d/).

The settings that may be configured are:

  • max_wait: the maximum amount of clock time in seconds that should be spent searching metadata_urls. A value less than zero will result in only one request being made, to the first in the list. (default: 120)
  • timeout: the timeout value provided to urlopen for each individual http request. This is used both when selecting a metadata_url and when crawling the metadata service. (default: 50)

An example configuration with the default values is provided below:

datasource:
  CloudStack:
    max_wait: 120
    timeout: 50