What is pseudo parameters in CloudFormation?
Pseudo parameters are parameters that are predefined by AWS CloudFormation. You don’t declare them in your template. Use them the same way as you would a parameter, as the argument for the Ref function.
How do you reference parameters in CloudFormation?
Referencing a parameter within a template You use the Ref intrinsic function to reference a parameter, and AWS CloudFormation uses the parameter’s value to provision the stack. You can reference parameters from the Resources and Outputs sections of the same template.
What is FN :: if?
Fn::Equals Compares if two values are equal. Returns true if the two values are equal or false if they aren’t.
What is FN :: sub?
Fn::Sub. The intrinsic function Fn::Sub substitutes variables in an input string with values that you specify. In your templates, you can use this function to construct commands or outputs that include values that aren’t available until you create or update a stack.
What is CloudFormation metadata?
Metadata keys Defines configuration tasks for the cfn-init helper script. This script is useful for configuring and installing applications on EC2 instances. For more information, see AWS::CloudFormation::Init .
What is FN in CloudFormation?
The intrinsic function Fn::Join appends a set of values into a single value, separated by the specified delimiter. If a delimiter is the empty string, the set of values are concatenated with no delimiter.
What is ref in CloudFormation?
The intrinsic function Ref returns the value of the specified parameter or resource. When you specify a parameter’s logical name, it returns the value of the parameter. When you specify a resource’s logical name, it returns a value that you can typically use to refer to that resource, such as a physical ID.
What’s an advantage of using parameters in a CloudFormation template?
What’s an advantage of using parameters in a CloudFormation template? Allow customizing a stack without changing the template. Why would you use CloudFormation to automatically create resources for a development environment instead of creating them using AWS CLI commands? (Select TWO.)
What is condition in CloudFormation?
The optional Conditions section contains statements that define the circumstances under which entities are created or configured. For example, you can create a condition and then associate it with a resource or output so that AWS CloudFormation only creates the resource or output if the condition is true.
What is FN equal to in physics?
There are two types of friction generally mentioned. One is static friction and the other is kinetic friction. Static friction is greater than kinetic friction. To find static friction, it equals the product of normal force (Fn) and static friction coefficient (Fs). F=Fn x Fs.
What is FN :: Base64?
The intrinsic function Fn::Base64 returns the Base64 representation of the input string. This function is typically used to pass encoded data to Amazon EC2 instances by way of the UserData property.
What is Yaml sub?
The intrinsic function Fn::Sub (YAML ! Sub) substitutes variables in an input string with values that you specify. In your templates, you can use this function to construct commands or outputs that include values that aren’t available until you create or update a stack.
What are pseudo parameters in AWS CloudFormation?
Pseudo parameters are parameters that are predefined by AWS CloudFormation. You don’t declare them in your template. Use them the same way as you would a parameter, as the argument for the Ref function. The following snippet assigns the value of the AWS::Region pseudo parameter to an output value:
What are the different types of CloudFormation parameters?
Outside of the custom parameters you define, there are several built-in parameter types included in CloudFormation. Typically, used to refer to existing AWS resources – there are AWS parameters for Key Pairs, Security Groups, and Subnets – to name just a few. You can find a complete list within the CloudFormation documentation.
What is a pseudo parameter?
Pseudo parameters are parameters that are predefined by AWS CloudFormation. You don’t declare them in your template. Use them the same way as you would a parameter, as the argument for the Ref function. The following snippet assigns the value of the AWS::Region pseudo parameter to an output value:
What is allowedvalues in CloudFormation?
AllowedValues: another property that provides a control mechanism for inputs in a parameter. You could use this to control the EC2 instance type and sizes in a template. Outside of the custom parameters you define, there are several built-in parameter types included in CloudFormation.