This is the new *CloudFormation Template Reference Guide*. Please update your bookmarks and links. For help getting started with CloudFormation, see the [AWS CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/Welcome.html).

# AWS::ServiceDiscovery::PrivateDnsNamespace
<a name="aws-resource-servicediscovery-privatednsnamespace"></a>

Creates a private namespace based on DNS, which is visible only inside a specified Amazon VPC. The namespace defines your service naming scheme. For example, if you name your namespace `example.com` and name your service `backend`, the resulting DNS name for the service is `backend.example.com`. Service instances that are registered using a private DNS namespace can be discovered using either a `DiscoverInstances` request or using DNS. For the current quota on the number of namespaces that you can create using the same AWS account, see [AWS Cloud Map quotas](https://docs.aws.amazon.com/cloud-map/latest/dg/cloud-map-limits.html) in the *AWS Cloud Map Developer Guide*.

## Syntax
<a name="aws-resource-servicediscovery-privatednsnamespace-syntax"></a>

To declare this entity in your CloudFormation template, use the following syntax:

### JSON
<a name="aws-resource-servicediscovery-privatednsnamespace-syntax.json"></a>

```
{
  "Type" : "AWS::ServiceDiscovery::PrivateDnsNamespace",
  "Properties" : {
      "[Description](#cfn-servicediscovery-privatednsnamespace-description)" : {{String}},
      "[Name](#cfn-servicediscovery-privatednsnamespace-name)" : {{String}},
      "[Properties](#cfn-servicediscovery-privatednsnamespace-properties)" : {{Properties}},
      "[Tags](#cfn-servicediscovery-privatednsnamespace-tags)" : {{[ Tag, ... ]}},
      "[Vpc](#cfn-servicediscovery-privatednsnamespace-vpc)" : {{String}}
    }
}
```

### YAML
<a name="aws-resource-servicediscovery-privatednsnamespace-syntax.yaml"></a>

```
Type: AWS::ServiceDiscovery::PrivateDnsNamespace
Properties:
  [Description](#cfn-servicediscovery-privatednsnamespace-description): {{String}}
  [Name](#cfn-servicediscovery-privatednsnamespace-name): {{String}}
  [Properties](#cfn-servicediscovery-privatednsnamespace-properties): {{
    Properties}}
  [Tags](#cfn-servicediscovery-privatednsnamespace-tags): {{
    - Tag}}
  [Vpc](#cfn-servicediscovery-privatednsnamespace-vpc): {{String}}
```

## Properties
<a name="aws-resource-servicediscovery-privatednsnamespace-properties"></a>

`Description`  <a name="cfn-servicediscovery-privatednsnamespace-description"></a>
A description for the namespace.  
*Required*: No  
*Type*: String  
*Maximum*: `1024`  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Name`  <a name="cfn-servicediscovery-privatednsnamespace-name"></a>
The name that you want to assign to this namespace. When you create a private DNS namespace, AWS Cloud Map automatically creates an Amazon Route 53 private hosted zone that has the same name as the namespace.  
*Required*: Yes  
*Type*: String  
*Pattern*: `^(?!arn:)[!-~]{1,253}$`  
*Maximum*: `253`  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

`Properties`  <a name="cfn-servicediscovery-privatednsnamespace-properties"></a>
Properties for the private DNS namespace.  
*Required*: No  
*Type*: [Properties](aws-properties-servicediscovery-privatednsnamespace-properties.md)  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Tags`  <a name="cfn-servicediscovery-privatednsnamespace-tags"></a>
The tags for the namespace. Each tag consists of a key and an optional value, both of which you define. Tag keys can have a maximum character length of 128 characters, and tag values can have a maximum length of 256 characters.  
*Required*: No  
*Type*: Array of [Tag](aws-properties-servicediscovery-privatednsnamespace-tag.md)  
*Minimum*: `0`  
*Maximum*: `200`  
*Update requires*: Updates are not supported.

`Vpc`  <a name="cfn-servicediscovery-privatednsnamespace-vpc"></a>
The ID of the Amazon VPC that you want to associate the namespace with.  
*Required*: Yes  
*Type*: String  
*Maximum*: `64`  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

## Return values
<a name="aws-resource-servicediscovery-privatednsnamespace-return-values"></a>

### Ref
<a name="aws-resource-servicediscovery-privatednsnamespace-return-values-ref"></a>

When you pass the logical ID of this resource to the intrinsic `Ref` function, `Ref` returns the value of `Id` for the namespace, such as `ns-e4anhexample0004`.

For more information about using the `Ref` function, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-ref.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-ref.html).

### Fn::GetAtt
<a name="aws-resource-servicediscovery-privatednsnamespace-return-values-fn--getatt"></a>

The `Fn::GetAtt` intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.

For more information about using the `Fn::GetAtt` intrinsic function, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html).

#### 
<a name="aws-resource-servicediscovery-privatednsnamespace-return-values-fn--getatt-fn--getatt"></a>

`Arn`  <a name="Arn-fn::getatt"></a>
The Amazon Resource Name (ARN) of the private namespace.

`HostedZoneId`  <a name="HostedZoneId-fn::getatt"></a>
The ID for the Route 53 hosted zone that AWS Cloud Map creates when you create a namespace.

`Id`  <a name="Id-fn::getatt"></a>
The ID of the private namespace.

## Examples
<a name="aws-resource-servicediscovery-privatednsnamespace--examples"></a>



### Create a private DNS namespace
<a name="aws-resource-servicediscovery-privatednsnamespace--examples--Create_a_private_DNS_namespace"></a>

The following example creates a private DNS namespace named `private-example.com`.

#### JSON
<a name="aws-resource-servicediscovery-privatednsnamespace--examples--Create_a_private_DNS_namespace--json"></a>

```
{
    "Resources": {
        "PrivateDnsNamespace": {
            "Type": "AWS::ServiceDiscovery::PrivateDnsNamespace",
            "Properties": {
                "Description": "AWS Cloud Map private DNS namespace for resources for example.com website",
                "Vpc": "vpc-12345678",
                "Name": "private-example.com",
                "Properties": {
                    "DnsProperties": {
                        "SOA": {
                            "TTL": 100
                        }
                    }
                }
            }
        }
    }
}
```

#### YAML
<a name="aws-resource-servicediscovery-privatednsnamespace--examples--Create_a_private_DNS_namespace--yaml"></a>

```
Resources:
  PrivateDnsNamespace:
    Type: AWS::ServiceDiscovery::PrivateDnsNamespace
    Properties:
      Description: AWS Cloud Map private DNS namespace for resources for example.com website
      Vpc: vpc-12345678
      Name: private-example.com
      Properties:
        DnsProperties:
          SOA:
            TTL: 100
```

## See also
<a name="aws-resource-servicediscovery-privatednsnamespace--seealso"></a>
+ [CreatePrivateDnsNamespace](https://docs.aws.amazon.com/cloud-map/latest/api/API_CreatePrivateDnsNamespace.html) in the * AWS Cloud Map API Reference *