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I modified a Canonical ubuntu image on a t1.micro sized instance, saved the EBS boot image, and am now trying to re-start it using a slightly larger instance.

The only instances available (for regular and spot requests) are:

  • t1.micro
  • m1.large
  • etc...

Why can I not start an m1.small or m1.medium sized instance?

Micro instances are too weak, but a m1.large is too powerful...

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Annoying, isn't it... I wish Amazon had explained themselves on this one. – romkyns Dec 19 '11 at 15:33
up vote 4 down vote accepted

The t1.micro instance type supports both 32-bit and 64-bit AMIs.

m1.small and c1.medium only support 32-bit AMis at this time.

All the rest (larger) instance types only support 64-bit AMIs.

You created a 64-bit AMI, so it will run on t1.micro and the larger instance types, but not on m1.small or c1.medium. You would need to create a 32-bit AMI to run on those types (including t1.micro which can run either).

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Thanks, Eric. I love Alestic! – darkAsPitch Nov 7 '11 at 18:09
darkAsPitch: What AMI id did you start with? or what Ubuntu release are you running? – Eric Hammond Nov 7 '11 at 19:18
I started with ami-bbf539d2 (Ubuntu 11.10 Oneiric Server 64 Bit) and have just migrated to ami-a7f539ce (Ubuntu 11.10 Oneiric Server 64 Bit) and am running a c1.medium instance now. It works great, thank you. – darkAsPitch Nov 7 '11 at 20:17
darkAsPitch: I've edited your question to clarify that you are using AMIs built and published by Canonical. I list their Ubuntu AMI ids at the top of but I have migrated the publishing responsibility to Canonical and they have resources dedicated to supporting this process. – Eric Hammond Nov 8 '11 at 1:30

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