Difference between revisions of "XenServerRescue"

Latest revision as of 23:30, 17 February 2013

Summary

The ability to boot from a rescue image and mount the original virtual machine's disk as a secondary block device. System could have a standard rescue image or use the same base image and the instance being rescued.

Release Note

This functionality will give a user the ability to mount their instance's disk to a temporary "rescue" instance in the event that the instance becomes unbootable.

Rationale

Users need the ability to access their data in the event of the instance becoming unbootable.

User stories

John accidentally wipes a critical configuration file or directory from his instance, which prevents it from booting. John will need the ability to "rescue" his file system by spawning a temporary instance, attaching his original instance's VBD to it and then making any necessary repairs.

Assumptions

Design

Rescue

shut down instance
spawn temporary instance
create temporary VBD
plug VBD into temporary instance
setup VNC console access to temporary instance

Unrescue

unplug VBD
destroy temporary VBD
destroy temporary instance
boot normal instance

Implementation

UI Changes

n/a

Code Changes

This will live in nova/virt/xenapi.

Migration

n/a

@@ Line 1: / Line 1: @@
-__NOTOC__
 == Summary ==
+The ability to boot from a rescue image and mount the original virtual machine's disk as a secondary block device. System could have a standard rescue image or use the same base image and the instance being rescued.
 == Release Note ==
-This section should include a paragraph describing the end-user impact of this change.  It is meant to be included in the release notes of the first release in which it is implemented.  (Not all of these will actually be included in the release notes, at the release manager's discretion; but writing them is a useful exercise.)
+This functionality will give a user the ability to mount their instance's disk to a temporary "rescue" instance in the event that the instance becomes unbootable.
-It is mandatory.
+== Rationale ==
-== Rationale ==
+Users need the ability to access their data in the event of the instance becoming unbootable.
 == User stories ==
+John accidentally wipes a critical configuration file or directory from his instance, which prevents it from booting. John will need the ability to "rescue" his file system by spawning a temporary instance, attaching his original instance's VBD to it and then making any necessary repairs.
 == Assumptions ==
@@ Line 16: / Line 20: @@
 == Design ==
-You can have subsections that better describe specific parts of the issue.
+'''Rescue'''
+* shut down instance
+* spawn temporary instance
+* create temporary VBD
+* plug VBD into temporary instance
+* setup VNC console access to temporary instance
+'''Unrescue'''
+* unplug VBD
+* destroy temporary VBD
+* destroy temporary instance
+* boot normal instance
 == Implementation ==
-This section should describe a plan of action (the "how") to implement the changes discussed. Could include subsections like:
 === UI Changes ===
-Should cover changes required to the UI, or specific UI that is required to implement this
+n/a
 === Code Changes ===
-Code changes should include an overview of what needs to change, and in some cases even the specific details.
+This will live in nova/virt/xenapi.
 === Migration ===
-Include:
+n/a
-* data migration, if any
-* redirects from old URLs to new ones, if any
-* how users will be pointed to the new way of doing things, if necessary.
 == Test/Demo Plan ==
-This need not be added or completed until the specification is nearing beta.
 == Unresolved issues ==
-This should highlight any issues that should be addressed in further specifications, and not problems with the specification itself; since any specification with problems cannot be approved.
-== BoF agenda and discussion ==
-Use this section to take notes during the BoF; if you keep it in the approved spec, use it for summarising what was discussed and note any options that were rejected.
-----
-[[Category:Spec]]