Comments on: The EC2 Instance Life Cycle

By: shlomo

shlomo — Sun, 21 Aug 2011 10:35:38 +0000

@Adrian,

EBS volumes can be attached and detached while the instance is “Running” or “Stopped”. Although you can detach the root EBS volume (on an EBS-backed instance) while the instance is Running, you probably don’t want to unless you really know what you’re doing (it has to do with the OS keeping open files on the root volume).

The decision about which type of instance – S3-backed (instance-store) or EBS-backed – is determined by the AMI. Launch an S3-backed AMI for an instance-store root volume instance, and launch an EBS-backed AMI for an EBS root volume.

By: Adrian

Adrian — Sun, 21 Aug 2011 04:05:52 +0000

darn good analysis here.
what about detaching the EBS ? during a stop. is that possible.
how to make a S3 backed instance.

By: shlomo

shlomo — Wed, 27 Oct 2010 14:44:38 +0000

@Nelson,

Autocscaling is only capable of launching new instances, not starting stopped instances. That’s a very interesting idea, though. It would require using your own autocscaling framework, not Amazon’s.

By: Nelson

Nelson — Wed, 27 Oct 2010 11:14:23 +0000

Thanks for the great post (especially the diagram explaining EBS boot).
Is it possible to use auto-scaling to automatically revive an EBS instance that has been stopped?

By: shlomo

shlomo — Sun, 12 Sep 2010 05:25:28 +0000

@Tobu,

Yes, it can take a few minutes. That SSH ProxyCommand is a cool idea, but it’s not appropriate for seldom-but-immediate need.

By: Tobu

Tobu — Fri, 10 Sep 2010 17:10:44 +0000

I asked ServerFault and it seems to fall in the one-three minute range, but with some variability and no guarantee that there is a machine available at all.

By: Tobu

Tobu — Thu, 09 Sep 2010 21:45:41 +0000

I wonder how long these transitions take. The new micro option is starting to look attractive for my modest needs. If I set my SSH ProxyCommand to ec2-run-instances or ec2-startup-instances (plus socat magic), how soon will the machine be available?

By: shlomo

shlomo — Sat, 10 Jul 2010 20:13:32 +0000

@tim,

Check out Eric Hammond’s article providing a few ways to prevent accidental termination from having drastic effects: http://alestic.com/2010/01/ec2-instance-locking

By: tim

tim — Sat, 10 Jul 2010 06:02:36 +0000

I found out the hard way that terminated instances with ebs boot partition cannot be restarted, haha. luckily it was just during a test, so nothing was lost.

Thanks for your article, good casual read.

By: Persistence Strategies for Amazon EC2 – The Server Labs Blog

Persistence Strategies for Amazon EC2 – The Server Labs Blog — Thu, 08 Jul 2010 14:02:37 +0000

[...] EBS-backed AMI [2]. These two AMIs exhibit a number of differences, for example in their lifecycle [3] and data persistence characteristics [...]