Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I created a custom AMI based on the Ubuntu 11.10 64-bit AMI from Amazon. When I try to start it up, I get an error:

ec2-run-instances -t t1.micro ami-c0b368a9 -k showcase -z us-east-1a

Client.InvalidParameterValue: The requested instance type's architecture (i386) does not match the architecture in the manifest for aki-825ea7eb (x86_64)

When I look in the FAQs here:

it says "All instance types can run 64-bit AMIs."

How can I start a 64-bit AMI?

I'm running ec2-api-tools and ec2-ami-tools 1.3-45758 on OSX.

Any help would be much appreciated.

*UPDATE:* I created the AMI incorrectly, when registering an AMI from a snapshot, I needed to provide --architecture x86_64 to the ec2-register command.

share|improve this question
up vote 4 down vote accepted

Your ami-c0b368a9 is 32-bit.

For some reason, it was registered with a 64-bit kernel image (aki-825ea7eb).

Your AMI and AKI need to match in architecture.

You could simply specify a 32-bit kernel to run with the 32-bit AMI, but it's probably best to build and register the AMI correctly.

share|improve this answer
Thanks after thinking about your answer "register the AMI correctly" I found that I can specify the architecture on the command line for ec2-register: > ec2-register -s snap-56b3ca2b --kernel aki-825ea7eb --architecture x86_64 --description "Web2py 1.99.7 base install with nginx, uwsgi, rabbitmq 2.8.1" --name "web2py-1.99.7_nginx_uwsgi_v2" – Robin Apr 18 '12 at 23:54

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.