CloudFormation alarm for multiple Lambdas

Question

I have an app with a bunch of Lambdas. Instead of adding one CloudWatch alarm for each is there a way to combine all of them into one alarm that goes off if any of the Lambdas error out?

So far I tried:

• Adding each function as a dimension (CloudFormation complains about duplicate FunctionNames)
• Adding each function as a dimension with a different key than FunctionName, CloudFormation doesn't complain, but it doesn't really work either.

Answer 1

One possible solution is to use Metrics and combine all dimensions using Expression: MAX([d1,d2,...]). Just make sure to pass 'ReturnData: false' on the other metrics.