aws-cloudformation / aws-cloudformation/cloudformation-coverage-roadmap
AWS::EC2::PrefixList - [BUG] - You cannot modify the entries and the maximum number of entries for the prefix list in the same request.
- Dominant language
- No language data
- Stars
- 1.1k
- Forks
- 62
- PR merge metrics
- No merged PRs in 30d
Description
### Name of the resource
AWS::EC2::PrefixList
### Resource Name
AWS::EC2::PrefixList
### Issue Description
Currently any modification into PrefixList you cannot modify the size and entries at the same time. If you use CDK codes to generate the PrefixLIst. the size is automatically set by the code base on your entries size.
While this is limitation part of PrefixList API. The CloudFormation can incorrectly fail with false positive to not recognize size no longer need to be updated in same request.
To successfully update the CloudFormation we will need to perform the following tasks:
1. manually update the prefix list via AWS Console/CLI/API.
- Update prefix list size
- Update prefix list entries to match EXACTLY the same entries in CloudFormation (include entries description. any typo can cause it fail)
2. Push our CloudFormation changes
This manual update also cause issues:
1. PrefixList cannot effectively manage by CloudFormation/CDK
2. If any CloudFormation fail and rollback happen. It re-trigger the error say cannot modify entries and resize in same request. This can also cause of other roll back fail and lot of manual fix require
3. breaking the Infrustructure as Code requirement where little to no human involvement as possible (especially if we operate a strict secure compliance environment where there are limited permission outside of IaC pipeline. this made the resource unsuable for management)
### Expected Behavior
CloudFormation resource should:
1. should be able to recognize size not need to be update any more if prefix list already updated
2. Cfn resource should be able to handle resize and update entries. This should be possible be coded as part of the CloudFormation resources
### Observed Behavior
CloudFormation return error when try to update entries and size
### Test Cases
Update the resource with new size and entries
### Other Details
_No response_
Contributor guide
Research direction
No repository files or automated tests are named. Start by reproducing an AWS::EC2::PrefixList update that changes both maximum size and entries, then review the CloudFormation resource behavior around the reported API limitation. Done means the resource recognizes when resizing is unnecessary and can update size and entries without manual AWS Console or CLI steps, including rollback handling.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- aws
- Domain
- cloud
- Issue type
- Bug
- Difficulty
- 5/5
- Estimated time
- Over a week
- Activity status
- Quiet
- Clarity
- Mostly clear
- Newbie friendliness
- 42/100