# Learn about common RFC parameters
Common RFC parameters

The following are RFC parameters that you are required to submit, and parameters that are commonly used in RFCs:
+ Change type information: ChangeTypeId and ChangeTypeVersion. Ror a list of change type IDs and version numbers, see [Change Type Reference](https://docs.aws.amazon.com/managedservices/latest/ctref/index.html). 

  Run `list-change-type-classification-summaries` in the CLI with the `query` argument to narrow the results. For example, narrow results to change types that contain "Access" in the `Item` name.

  ```
  aws amscm list-change-type-classification-summaries --query "ChangeTypeClassificationSummaries [?contains (Item, 'access')].[Category,Subcategory,Item,Operation,ChangeTypeId]" --output table
  ```

  Run `get-change-type-version` and specify the change type ID. The following command gets the CT version for ct-2tylseo8rxfsc. 

  ```
  aws amscm get-change-type-version --change-type-id ct-2tylseo8rxfsc
  ```
+ Title: A name for the RFC; this becomes the **Subject** of the RFC in the AMS console RFC list and you can search on it with the `GetRfc` command and a filter on `Title`
+ Scheduling: If you want a scheduled RFC, you must include the `RequestedStartTime` and `RequestedEndTime` parameters, or use the **Schedule this change** console option. For an **ASAP** RFC (that runs as soon as it's approved), when using the CLI, leave `RequestedStartTime` and `RequestedEndTime` null. When using the console, accept the **ASAP** option. 

  If the `RequestedStartTime` is missed, the RFC is rejected.
+ Provisioning CTs: The execution parameters, or `Parameters` are the specific settings that are required to provision the resource. They vary widely depending on the CT.
+ Non-provisioning CTs: CTs that do not provision a resource, such as access CTs or Other \$1 Other, or delete stack, have minimal execution parameters and no `Parameters` block.
+ Some RFCs also require that you specify a `TimeoutInMinutes`, or how many minutes are allowed for the creation of the stack before the RFC is failed. Valid values are 60 (minutes) up to 360, for long-running UserData. If the execution can't be completed before the `TimeoutInMinutes` is exceeded, the RFC fails. However, this setting doesn't delay the execution of the RFC.
+ RFCs that create instances, such as an S3 bucket or an ELB, generally provide a schema that allows you to add up to seven tags (key/value pairs). You can add more tags to your S3 bucket by submitting an RFC using the Deployment \$1 Advanced stack components \$1 Tag \$1 Create change type (ct-3cx7we852p3af). EC2, EFS, RDS, and the multi-tiered (HA Two-Tiered and HA One-Tiered) schemas allow up to fifty tags. Tags are specified in the `ExecutionParameters` part of the schema. Providing tags can be of great value. For more information, see [Tagging Your Amazon EC2 Resources](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/Using_Tags.html). 

  When using the AMS console, you must open the **Additional configuration** area in order to add tags.<a name="using-tags-tip"></a>
**Tip**  
Many CT schemas have a `Description` and `Name` field near the top of the schema. Those fields are used to name the stack or stack component, they don't name the resource you're creating. Some schemas offer a parameter to name the resource you're creating, and some do not. For example, the CT schema for Create EC2 stack doesn't offer a parameter to name the EC2 instance. In order to do so, you must create a tag with the key "Name" and the value of what you want the name to be. If you do not create such a tag, your EC2 instance displays in the EC2 console without a name attribute. 

## Use the RFC AWS Region option


The AMS API and CLI (`amscm` and `amsskms`) endpoints are in `us-east-1`. If you federate with Security Assertion Markup Language (SAML), then scripts are provided to you at onboarding that set your AWS Region to us-east-1. If you use SAML, then you don't need to specify the `--region` option when you issue a command. If your SAML is configured to use us-east-1 but your account isn't in that AWS Region, then you must specify your account-onboarded Region when you issue other AWS commands (for example, `aws s3`).

**Note**  
Most of the command examples provided in this guide don't include the `--region` option.