

Blue Green Deployment - jcsalterego
http://martinfowler.com/bliki/BlueGreenDeployment.html

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jbyers
Double the hardware can be an expensive proposition for a startup, unless
you're paying by the hour. I prefer red pill / blue pill deployment. Build an
environment where you incrementally deploy and roll back new code. During a
rollout some servers will run old code (blue), some servers will run new code
(red). This is what IMVU and others have described in their continuous
deployment processes, only with Matrix-friendly colors.

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jrockway
This seems like a problem unless your application is truly shared-nothing.
Imagine what happens if the red code puts a piece of data in the shared cache,
that is later retrieved by the blue code. The blue code gets confused, and
crashes (or more likely, subtly corrups some other piece of data, which
confuses the red code...)

Also, database schema issues, users wondering why a feature disappears when
they reload the page, etc.

Either are definitely improvements over the usual dev / staging / production
nightmare, though. (Sometimes I think people like that setup because their
lives are boring and hacking on the production site at 5am on a Saturday adds
much-needed excitement to their lives. I can't think of any technical reason
for it, anyway.)

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pibefision
Any insight about gems, git workflows or any other interesting bit to
implement it on Rails Apps?

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jcapote
This is pretty much what EngineYard does.

