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

# AWS::MemoryDB::SubnetGroup Tag
<a name="aws-properties-memorydb-subnetgroup-tag"></a>

A tag that can be added to an MemoryDB resource. Tags are composed of a Key/Value pair. You can use tags to categorize and track all your MemoryDB resources. When you add or remove tags on clusters, those actions will be replicated to all nodes in the cluster. A tag with a null Value is permitted. For more information, see [Tagging your MemoryDB resources](https://docs.amazonaws.cn/MemoryDB/latest/devguide/tagging-resources.html)

## Syntax
<a name="aws-properties-memorydb-subnetgroup-tag-syntax"></a>

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

### JSON
<a name="aws-properties-memorydb-subnetgroup-tag-syntax.json"></a>

```
{
  "[Key](#cfn-memorydb-subnetgroup-tag-key)" : {{String}},
  "[Value](#cfn-memorydb-subnetgroup-tag-value)" : {{String}}
}
```

### YAML
<a name="aws-properties-memorydb-subnetgroup-tag-syntax.yaml"></a>

```
  [Key](#cfn-memorydb-subnetgroup-tag-key): {{String}}
  [Value](#cfn-memorydb-subnetgroup-tag-value): {{String}}
```

## Properties
<a name="aws-properties-memorydb-subnetgroup-tag-properties"></a>

`Key`  <a name="cfn-memorydb-subnetgroup-tag-key"></a>
The key for the tag. May not be null.  
*Required*: Yes  
*Type*: String  
*Pattern*: `^(?!aws:)(?!memorydb:)[a-zA-Z0-9 _\.\/=+:\-@]{1,128}$`  
*Minimum*: `1`  
*Maximum*: `128`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`Value`  <a name="cfn-memorydb-subnetgroup-tag-value"></a>
The tag's value. May be null.  
*Required*: Yes  
*Type*: String  
*Pattern*: `^(?!aws:)(?!memorydb:)[a-zA-Z0-9 _\.\/=+:\-@]{1,256}$`  
*Minimum*: `1`  
*Maximum*: `256`  
*Update requires*: [No interruption](https://docs.amazonaws.cn/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)