nova/doc/source/api_ext/ext_rescue.rst

About The Rescue Extension

The rescue extension lets you put a server into a "rescue" status when the virtual instance will be replaced with a "rescue" image and have its existing drive attached as a second disk so that a root user can log in and troubleshoot problems with the virtual server.

To put a server into "rescue" state, you do not have to be an administrator. The only requirement is that the base image used to build your instance must still be available.

To obtain current information the extensions available to you, issue an EXTENSION query on the OpenStack system where it is installed, such as http://mycloud.com/v1.1/tenant/extensions.

Rescue Extension Overview

Name

Rescue

Namespace

http://docs.openstack.org/ext/rescue/api/v1.1

Alias

OPS-RES

Contact

Josh Kearney <josh@jk0.org>

Status

Alpha

Extension Version

v1.0 (2011-08-18)

Dependencies

Compute API 1.1

Doc Link (PDF)

http://

Doc Link (WADL)

http://

Short Description

This extension enables rescue capabilities for OpenStack Compute servers so that virtual instances running in the cloud may be put in a rescue status.

Sample Query Responses

As shown below, responses to an EXTENSION query in XML or JSON provide basic information about the extension.

Extension Query Response: XML:: N/A

Extension Query Response: JSON:

{"extensions": [{"updated": "2011-08-18T00:00:00+00:00", "name": "Rescue", "links": [], "namespace": "http://docs.openstack.org/ext/rescue/api/v1.1", "alias": "os-rescue", "description": "Instance rescue mode"}]}

Document Change History

Revision Date	Summary of Changes
2011-09-16	Initial draft

Summary of Changes

This extension to the OpenStack Compute API enables rescue of running instances.

To support these new actions, the extension also issues new states.

New Actions ----------rescue unrescue

New Faults

None

New Headers

None

New Resources

None

New States

RESCUING UNRESCUING

Changes to the Cloud Servers Specification

A new action added to the 4.3 Server Actions section.

Rescue Server

Verb	URI
POST	/servers/id/rescue

Normal Response Code(s): 202

Error Response Code(s): computeFault (400, 500, …), serviceUnavailable (503), unauthorized (401), forbidden (403), badRequest (400), badMethod (405), overLimit (413), itemNotFound (404), badMediaType (415), buildInProgress (409)

Status Transition: ACTIVE -> RESCUING -> ACTIVE

This operation places the server into RESCUING status.