By using AWS re:Post, you agree to the Terms of Use

Event bus: UPDATE_FAILED: Unsupported Operation


All of a sudden we started to get UPDATE_FAILED errors with "Unsupported Operation" error message for the event bus.

We use infra-as-code (CDK) approach and I am tracking the changes, and there were NO infra changes, other than tags changing (e.g. build ID, git sha).

I am also doing a cdk diff and it produces no meaningful changes, other than tags.

Yet, CloudFormation has been failing for days with the aforementioned message.

We most definitely did not make any changes to event bridge (bus) itself or anything surrounding that.

Any ideas?

  • You are not alone as this same thing happened with our CDK deployed event bus deployments. Yesterday when we went to release latest fixes to production it failed with this same "Unsupported Operation" error with no further detail and this is now happening on all updates when tested on multiple previously deployable versions and on multiple AWS accounts.

  • That is super annoying! Thanks for the confirmation. Have you reached out to support yet?

  • Same issue on a standard AWS stack, using SAM, any solution / workaround ? It's getting very problematic

  • Same issue using SAM: I have to first manually delete my stack every time I need to update it, which is absolutely not feasible on production environments.

  • Same issue with CDK, I'm currently unable to deploy anything as my Stack containing the EventBus has a tag with my commit sha, so anything I deploy is seen as a change and is failing.

2 Answers
Accepted Answer

Got a response from the Amazon support team:

To begin with I would like to inform you that this is a known issue by our CloudFormation service team, and they are already working on a fix for this issue. The issue is caused by updating stack-level tags(not resource level tags i.e., even without specifically having made changes to the resource) on “AWS::Events::EventBus” resource type. The current workaround is to not make any changes to the stack-level tags used by any stacks containing an “AWS::Events::EventBridge“ resource. This will result in this resource not being updated thus allowing you to resume with update of your stacks without facing this error.

Also, we were able to replicate the scenario at our end. We created a stack with an "AWS::Events::EventBus" resource with Resource Level Tags and no error was shown after multiple updates requested. However, when we tried to add Stack Level Tags, we encountered the same error you are facing. Hence, it is confirmed that the issue is with the "Stack level tags".

Unfortunately, I’m not able to provide ETA on when this issue might be fixed since AWS Support Engineers are not privy to development road-maps. I would like to apologize for the inconvenience caused.

Rest assured, I will keep the case in Pending Amazon Action and I will keep you updated on the resolution of this issue as soon as I have an update from the internal Team.

answered 12 days ago
  • I got the same support response as you and while they haven't yet reported that it is fixed it worked fine for me now and all my production deployments are now completed with no issues. So it seems their internal team has already made the change to resolve the issue.


By specifying stack failure options, you can troubleshoot resources in a CREATE_FAILED or UPDATE_FAILED status. You can provision failure options for all stack deployments and change set operations. Is it possible to view the stack events to see any associated error messages with the aws cloudformation describe-stack-events command.

Link - -- [1]

To roll back a stack from the CREATE_FAILED or UPDATE_FAILED stack status Specify the rollback-stack operation to roll back a stack to its last stable state. Initiate a rollback with the rollback-stack operation and specify the stack name.

aws cloudformation rollback-stack --stack-name myteststack

Hope this helps !!

answered 14 days ago
  • By specifying stack failure options

    Which options should I specify?

    Is it possible to view the stack events to see any associated error messages with the aws cloudformation describe-stack-events command.

    I can already see all of the events in the CF console UI. Is it not the same?

    The event says "Unsupported Operation".

You are not logged in. Log in to post an answer.

A good answer clearly answers the question and provides constructive feedback and encourages professional growth in the question asker.

Guidelines for Answering Questions