{"id":4295,"date":"2021-04-11T09:44:45","date_gmt":"2021-04-11T07:44:45","guid":{"rendered":"http:\/\/miro.borodziuk.eu\/?p=4295"},"modified":"2024-05-24T15:41:31","modified_gmt":"2024-05-24T13:41:31","slug":"cloudformation-5","status":"publish","type":"post","link":"http:\/\/miro.borodziuk.eu\/index.php\/2021\/04\/11\/cloudformation-5\/","title":{"rendered":"CloudFormation – 5 – Parameters"},"content":{"rendered":"

<\/p>\n

Parameters from SSM<\/span><\/p>\n

Consider such a yaml template:<\/p>\n

# this will pickup the latest value of the parameter every time the template is run\r\n# the parameter value must be the Key for that Parameter. Then CFN will retrieve the value\r\n# this does not support SecureString SSM Parameter types\r\nParameters:\r\n  InstanceType:\r\n    Type: 'AWS::SSM::Parameter::Value<String>'\r\n    Default: \/EC2\/InstanceType\r\n\r\n  ImageId: \r\n    Type: 'AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>'\r\n    Default: \/EC2\/AMI_ID\r\n\r\nResources:\r\n  # this instance will be automatically updated \r\n  # when we change the parameter in SSM ourselves\r\n  # and then run the CloudFormation template\r\n  MyInstanceWithParameters:\r\n    Type: AWS::EC2::Instance\r\n    Properties:\r\n      ImageId: !Ref ImageId\r\n      InstanceType: !Ref InstanceType\r\n<\/pre>\n
Now let’s create the parameteres in SSM:<\/p>\n
AWS Systems Manager -> Parameter Store -> Create parameter<\/code><\/p>\n
\"\"<\/p>\n
Now go and create the second parameter. First copy the AMI Id.<\/p>\n
\"\"<\/p>\n
And create parameter:<\/p>\n
\"\"<\/p>\n
Create -><\/code><\/p>\n
\"\"<\/p>\n
And now go and create the stack<\/p>\n
\"\"<\/p>\n
Next -><\/code><\/p>\n
The stack is being created. On the parameteres tab we see used parameteres and the values:<\/p>\n
\"\"<\/p>\n
When we go to the created EC2 instance we see that instance type and the AMI is which was selected:<\/p>\n
\"\"<\/p>\n
 <\/p>\n
Now let’s change the value of an AMI parameter:<\/p>\n
\"\"<\/p>\n
\"\"<\/p>\n
And update the stack:<\/p>\n
\"\"<\/p>\n
Next -> Next -><\/p>\n
\"\"<\/p>\n
AMI of EC2 instance has been changed:<\/p>\n
\"\"<\/p>\n
 <\/p>\n
Public Parameters from SSM<\/span><\/p>\n
Some AWS services publish information about common artifacts as AWS Systems Manager public<\/em> parameters. For example, the Amazon Elastic Compute Cloud (Amazon EC2) service publishes information about Amazon Machine Images (AMIs) as public parameters.<\/p>\n
Consider such a yaml template:<\/p>\n
# this will pickup the latest value of the parameter every time the template is run\r\n# the parameter value must be the Key for that Parameter. Then CFN will retrieve the value\r\n# this does not support SecureString SSM Parameter types\r\nParameters:\r\n  LatestLinuxAmiId:\r\n    Type: 'AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>'\r\n    # obtain list with\r\n    # aws ssm get-parameters-by-path --path \/aws\/service\/ami-amazon-linux-latest  --query 'Parameters[].Name'\r\n    Default: '\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-hvm-x86_64-gp2'\r\n\r\n  # this works for Windows too\r\n  LatestWindowsAmiId:\r\n    Type: 'AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>'\r\n    # obtain list with\r\n    # aws ssm get-parameters-by-path --path \"\/aws\/service\/ami-windows-latest\" --region us-east-1\r\n    Default: '\/aws\/service\/ami-windows-latest\/Windows_Server-2016-English-Core-Base'\r\n\r\nResources:\r\n  # this instance will be automatically updated \r\n  # when AWS releases a new AMI\r\n  # and then run the CloudFormation template\r\n  MyInstanceWithParameters:\r\n    Type: AWS::EC2::Instance\r\n    Properties:\r\n      ImageId: !Ref LatestLinuxAmiId\r\n      InstanceType: t2.micro\r\n<\/pre>\n
To obtain the list of all available linux AMI by AWS:<\/p>\n
C:\\Users\\mirth>aws ssm get-parameters-by-path --path \/aws\/service\/ami-amazon-linux-latest --query \"Parameters[].Name\"\r\n[\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-hvm-x86_64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-hvm-x86_64-gp2\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-hvm-x86_64-s3\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-minimal-hvm-x86_64-s3\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-minimal-pv-x86_64-s3\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-pv-x86_64-s3\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-hvm-arm64-gp2\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-hvm-x86_64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-hvm-x86_64-gp2\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-minimal-hvm-arm64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-minimal-hvm-x86_64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-minimal-pv-x86_64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn-ami-pv-x86_64-ebs\",\r\n    \"\/aws\/service\/ami-amazon-linux-latest\/amzn2-ami-minimal-hvm-x86_64-ebs\"\r\n]\r\n<\/pre>\n
Or all available Windows AMI:<\/p>\n
C:\\Users\\mirth>aws ssm get-parameters-by-path --path \"\/aws\/service\/ami-windows-latest\" --region eu-central-1\r\n{\r\n    \"Parameters\": [\r\n        {\r\n            \"Name\": \"\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Chinese_Simplified-64Bit-Base\",\r\n            \"Type\": \"String\",\r\n            \"Value\": \"ami-0ba5ffc543cb0f4b9\",\r\n            \"Version\": 66,\r\n            \"LastModifiedDate\": \"2021-06-11T02:09:00.341000+02:00\",\r\n            \"ARN\": \"arn:aws:ssm:eu-central-1::parameter\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Chinese_Simplified-64Bit-Base\",\r\n            \"DataType\": \"text\"\r\n        },\r\n        {\r\n            \"Name\": \"\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Chinese_Traditional-64Bit-Base\",\r\n            \"Type\": \"String\",\r\n            \"Value\": \"ami-0b71756f3f2cb18d1\",\r\n            \"Version\": 66,\r\n            \"LastModifiedDate\": \"2021-06-11T02:09:18.679000+02:00\",\r\n            \"ARN\": \"arn:aws:ssm:eu-central-1::parameter\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Chinese_Traditional-64Bit-Base\",\r\n            \"DataType\": \"text\"\r\n        },\r\n        {\r\n            \"Name\": \"\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Dutch-64Bit-Base\",\r\n            \"Type\": \"String\",\r\n            \"Value\": \"ami-0104d8db9b2ce0abf\",\r\n            \"Version\": 66,\r\n            \"LastModifiedDate\": \"2021-06-11T02:09:36.595000+02:00\",\r\n            \"ARN\": \"arn:aws:ssm:eu-central-1::parameter\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Dutch-64Bit-Base\",\r\n            \"DataType\": \"text\"\r\n        },\r\n        {\r\n            \"Name\": \"\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Hungarian-64Bit-Base\",\r\n            \"Type\": \"String\",\r\n            \"Value\": \"ami-000f505b6d84d1fe8\",\r\n            \"Version\": 65,\r\n            \"LastModifiedDate\": \"2021-06-11T02:11:59.592000+02:00\",\r\n            \"ARN\": \"arn:aws:ssm:eu-central-1::parameter\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Hungarian-64Bit-Base\",\r\n            \"DataType\": \"text\"\r\n        },\r\n        {\r\n            \"Name\": \"\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Japanese-64Bit-Base\",\r\n            \"Type\": \"String\",\r\n            \"Value\": \"ami-0ad37555d48e09d90\",\r\n            \"Version\": 66,\r\n            \"LastModifiedDate\": \"2021-06-11T02:12:19.789000+02:00\",\r\n            \"ARN\": \"arn:aws:ssm:eu-central-1::parameter\/aws\/service\/ami-windows-latest\/Windows_Server-2012-R2_RTM-Japanese-64Bit-Base\",\r\n            \"DataType\": \"text\"\r\n        },\r\n        {\r\n-- More  --<\/pre>\n
Let’s go and run this template:<\/p>\n
\"\"<\/p>\n
Next-><\/code><\/p>\n
\"\"<\/p>\n
Next -> Next<\/code><\/p>\n
\"\"<\/p>\n
Create stack -><\/code><\/p>\n
As we see the value of the parameters has been resolved:<\/p>\n
\"\"<\/p>\n
Read more at: https:\/\/docs.aws.amazon.com\/systems-manager\/latest\/userguide\/parameter-store-public-parameters.html<\/p>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":4331,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[89],"tags":[],"_links":{"self":[{"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/posts\/4295"}],"collection":[{"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/comments?post=4295"}],"version-history":[{"count":16,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/posts\/4295\/revisions"}],"predecessor-version":[{"id":4334,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/posts\/4295\/revisions\/4334"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/media\/4331"}],"wp:attachment":[{"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/media?parent=4295"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/categories?post=4295"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/miro.borodziuk.eu\/index.php\/wp-json\/wp\/v2\/tags?post=4295"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}