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If your instance is not listed it means you will not be able to use this process to update to Ubuntu Pro. Otherwise you can continue with the Ensure SSM is installed and functioning correctly and the instance is running, otherwise you won't be able to continue with this process.
2) Confirm ubuntu-advantage-tools is up to date
Doing this one instance at a time, connect to the instance using session manager and run the command below to confirm that ubuntu-advantage-tools is up to date.
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As long as the output in the terminal matches the above image, you can be assured that the update was successful and validated.
Resources
Canonical on the AWS Marketplace https://aws.amazon.com/marketplace/pp/prodview-36njlpsau6luw?sr=0-0&ref_=ucaf&applicationId=AWSMPContessa
Canonical Instructional Video https://www.youtube.com/watch?v=oYS28kmur2k&pp=ygUOdWJ1bnR1IGNoYW5uZWw%3D')
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