# Create a reverse DNS record for email on Amazon EC2
<a name="Using_Elastic_Addressing_Reverse_DNS"></a>

If you intend to send email to third parties from an EC2 instance, we recommend that you provision one or more Elastic IP addresses and assign static reverse DNS records to the Elastic IP addresses that you use to send email. This can help you avoid having your email flagged as spam by some anti-spam organizations. AWS works with ISPs and internet anti-spam organizations to reduce the chance that your email sent from these addresses will be flagged as spam.

**Considerations**
+ Before you create a reverse DNS record, you must set a corresponding forward DNS record (record type A) that points to your Elastic IP address.
+ If a reverse DNS record is associated with an Elastic IP address, the Elastic IP address is locked to your account and cannot be released from your account until the record is removed.
+ If you contacted Support to set up reverse DNS for an Elastic IP address, you can remove the reverse DNS, but you can't release the Elastic IP address because it is locked by Support. To unlock the Elastic IP address, contact [AWS Support](https://console.aws.amazon.com/support/home#/). After the Elastic IP address is unlocked, you can release it.
+ [AWS GovCloud (US) Region] You can't create a reverse DNS record. AWS must assign the static reverse DNS records for you. Open a support case to remove reverse DNS and email sending limitations. You must provide your Elastic IP addresses and reverse DNS records.

## Create a reverse DNS record
<a name="eip-create-rdns-record"></a>

You can create a reverse DNS record for your Elastic IP address as follows.

------
#### [ Console ]

**To create a reverse DNS record**

1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).

1. In the navigation pane, choose **Elastic IPs**.

1. Select the Elastic IP address and choose **Actions**, **Update reverse DNS**.

1. For **Reverse DNS domain name**, enter the domain name.

1. Enter **update** to confirm.

1. Choose **Update**.

------
#### [ AWS CLI ]

**To create a reverse DNS record**  
Use the [https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-address-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/modify-address-attribute.html) command.

```
aws ec2 modify-address-attribute \
    --allocation-id eipalloc-abcdef01234567890 \
    --domain-name example.com
```

The following is example output.

```
{
    "Addresses": [
        {
            "PublicIp": "192.0.2.0",
            "AllocationId": "eipalloc-abcdef01234567890",
            "PtrRecord": "example.net.",
            "PtrRecordUpdate": {
                "Value": "example.com.",
                "Status": "PENDING"
            }
        }
    ]
}
```

------
#### [ PowerShell ]

**To create a reverse DNS record**  
Use the [https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2AddressAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Edit-EC2AddressAttribute.html) cmdlet.

```
Edit-EC2AddressAttribute `
    -AllocationId 'eipalloc-abcdef01234567890' `
    -DomainName 'example.com' |
Format-List `
    AllocationId, PtrRecord, PublicIp,
    @{Name='PtrRecordUpdate';Expression={$_.PtrRecordUpdate | Format-List | Out-String}}
```

The following is example output.

```
AllocationId    : eipalloc-abcdef01234567890
PtrRecord       : example.net.
PublicIp        : 192.0.2.0
PtrRecordUpdate : 
                  Reason :
                  Status : PENDING
                  Value  : example.com.
```

------

## Remove a reverse DNS record
<a name="eip-remove-rdns-record"></a>

You can remove a reverse DNS record from your Elastic IP address as follows.

If you receive the following error, you can submit a [Request to remove email sending restrictions](https://repost.aws/knowledge-center/ec2-port-25-throttle) to Support for assistance.

```
The address cannot be released because it is locked to your account.
```

------
#### [ Console ]

**To remove a reverse DNS record**

1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).

1. In the navigation pane, choose **Elastic IPs**.

1. Select the Elastic IP address and choose **Actions**, **Update reverse DNS**.

1. For **Reverse DNS domain name**, clear the domain name.

1. Enter **update** to confirm.

1. Choose **Update**.

------
#### [ AWS CLI ]

**To remove a reverse DNS record**  
Use the [https://docs.aws.amazon.com/cli/latest/reference/ec2/reset-address-attribute.html](https://docs.aws.amazon.com/cli/latest/reference/ec2/reset-address-attribute.html) command.

```
aws ec2 reset-address-attribute \
    --allocation-id eipalloc-abcdef01234567890 \
    --attribute domain-name
```

The following is example output.

```
{
    "Addresses": [
        {
            "PublicIp": "192.0.2.0",
            "AllocationId": "eipalloc-abcdef01234567890",
            "PtrRecord": "example.com.",
            "PtrRecordUpdate": {
                "Value": "example.net.",
                "Status": "PENDING"
            }
        }
    ]
}
```

------
#### [ PowerShell ]

**To remove a reverse DNS record**  
Use the [https://docs.aws.amazon.com/powershell/latest/reference/items/Reset-EC2AddressAttribute.html](https://docs.aws.amazon.com/powershell/latest/reference/items/Reset-EC2AddressAttribute.html) cmdlet.

```
Reset-EC2AddressAttribute `
    -AllocationId 'eipalloc-abcdef01234567890' `
    -Attribute domain-name |
Format-List `
    AllocationId, PtrRecord, PublicIp,
    @{Name='PtrRecordUpdate';Expression={$_.PtrRecordUpdate | Format-List | Out-String}}
```

The following is example output.

```
AllocationId    : eipalloc-abcdef01234567890
PtrRecord       : example.com.
PublicIp        : 192.0.2.0
PtrRecordUpdate : 
                  Reason :
                  Status : PENDING
                  Value  : example.net.
```

------