Difference between revisions of "Heat/Blueprints/RollingUpdates"
(No difference)
|
Revision as of 00:34, 8 February 2013
- Launchpad Entry: HeatSpec:rolling-updates
- Created: 07 Feb 2013
- Contributors: Clint Byrum
Summary
While managing a large group of instances, I may want to roll out changes in topology and/or configuration to a limited percentage of these instances and then wait to see if those initial rollouts produced failures or successes before deploying a larger percentage. This is known as a "canary" deployment strategy, after the old mining practice of carrying a canary in a lantern to test for air quality.
Release Note
Multi-Instance resources may now specify a property which causes them to apply updates using a rolling or canary strategy.
Rationale
With large scale deployments, updating configuration on all machines at once without testing may result in downtime. Being able to control the deployment will lead to more reliability for users who implement it.
User stories
As an operations engineer I want to roll out a change to topology or configuration on a very large resource without the risk of significant downtime or error rates.
Assumptions
Design
[in progress]
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
Code Changes
Code changes should include an overview of what needs to change, and in some cases even the specific details.
Migration
Include:
- 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.
