AWS EC2 Instance Migration and AMI Sharing
Migrating an EC2 Instance Across Availability Zones (AZs)
- Objective: Move an EC2 instance from one AZ to another within the same region.
- Method: Use Amazon Machine Images (AMIs).
- Steps:
- Create an AMI from the existing EC2 instance.
- Launch a new EC2 instance in a different AZ using the created AMI.
Example:
- Original instance in
us-east-1a.
- Create AMI.
- Launch new instance from AMI in
us-east-1b.
Cross-Account AMI Sharing
- Purpose: Share AMIs with another AWS account.
- Ownership: Sharing does not change the ownership of the AMI.
- Conditions for Sharing:
- Unencrypted volumes can be shared with other accounts or publicly.
- Encrypted volumes require the volume to be encrypted with a customer-managed key (CMK).
Sharing Unencrypted AMIs
- Scenario: Account A shares an unencrypted AMI with Account B.
- Outcome: Account B can directly launch an EC2 instance from the shared AMI.
Sharing Encrypted AMIs
- Scenario: Account A shares an encrypted AMI, encrypted with CMK-A, with Account B.
- Requirements:
- Share the AMI with Account B.
- Share the corresponding KMS key (CMK-A) with Account B.
- Grant permissions to Account B to describe, decrypt, and re-encrypt using CMK-A
Cross-Account AMI Copy