AWS Automation Document not updating Lambda Alias - aws-lambda

Question

I've created an Automation Document using cloud formation to update the live alias for a given function. It runs ok without any errors and I'm not seeing anything cloud trail. But when I check which version is set to alias:live it is left unchanged.
template.yml
AWSTemplateFormatVersion: "2010-09-09"
Description: "AWS CloudFormation Template for Response Plans"
Parameters:
Environment:
Type: String
Default: "sandbox"
Domain:
Type: String
Team:
Type: String
NotificationARN:
Type: AWS::SSM::Parameter::Value<String>
Resources:
ResponsePlan:
Type: AWS::SSMIncidents::ResponsePlan
Properties:
Actions:
- SsmAutomation:
RoleArn: !GetAtt Role.Arn
DocumentName: UpdateAliasDocument
DisplayName: "UpdateLambdaAlias"
IncidentTemplate:
Impact: 3
NotificationTargets:
- SnsTopicArn:
Ref: NotificationARN
Summary: "String"
Title: "String"
Name: "UpdateLambdaAlias"
Tags:
- Key: "Team"
Value: !Ref Team
- Key: "Domain"
Value: !Ref Domain
- Key: "Environment"
Value: !Ref Environment
Document:
Type: AWS::SSM::Document
Properties:
Content:
schemaVersion: "2.2"
parameters:
FunctionVersion:
type: "String"
default: "1"
FunctionName:
type: "String"
mainSteps:
- name: "UpdateLambdaAlias"
action: aws:runShellScript
inputs:
runCommand:
- aws lambda update-alias --function-name {{FunctionName}} --name live --function-version {{FunctionVersion}}
DocumentType: "Command"
TargetType: /
Tags:
- Key: "Team"
Value: !Ref Team
Role:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Statement:
- Effect: Allow
Principal:
Service:
- lambda.amazonaws.com
Action: sts:AssumeRole
Path: /
Policies:
- PolicyName: EC2Instances
PolicyDocument:
Statement:
- Effect: Allow
Action:
- ec2:*
Resource:
- !Sub arn:${AWS::Partition}:ec2:${AWS::Region}:${AWS::AccountId}:instance/*
- PolicyName: UpdateAliasPolicy
PolicyDocument:
Statement:
- Effect: Allow
Action:
- lambda:UpdateFunctionConfiguration
Resource:
- !Sub arn:${AWS::Partition}:lambda:${AWS::Region}:${AWS::AccountId}:function:${Environment}-*
Instance:
Type: AWS::EC2::Instance
Properties:
ImageId: ami-0c2b8ca1dad447f8a
InstanceType: t2.micro
Monitoring: true
Tags:
- Key: "Team"
Value: !Ref Team
Update
Looks like not target is being found to run the script on

Answer 1

It looks like your Role entry does not have the required permissions to execute the update-alias command. Your policy only allows for lambda:UpdateFunctionConfiguration.
You will at least need the lambda:UpdateAlias permission as well. If this is not enough, you could try being very permissive with your role and then reducing the permissions afterwards.