How to determine your AWS Lambda@Edge regions and find your CloudWatch logs

You must review AWS CloudWatch log files in the correct region to see the log files created when CloudFront executed your Lambda function. I found this very usefull bash AWS CLI based bash command here which allows to determine a list of Regions where your Lambda@Edge function have received traffic so storing for future (personal) reference.

FUNCTION_NAME=function_name_without_qualifiers
for region in $(aws --output text  ec2 describe-regions | cut -f 3) 
do
    for loggroup in $(aws --output text  logs describe-log-groups --log-group-name "/aws/lambda/us-east-1.$FUNCTION_NAME" --region $region --query 'logGroups[].logGroupName')
    do
        echo $region $loggroup
    done
done

You can just leave FUNCTION_NAME empty to get a list of all functions.

References

• Testing and Debugging Lambda@Edge Functions @ AWS