# Using Amazon Route 53 as the DNS service for subdomains without migrating the parent domain
Amazon Route 53 provides flexibility in managing DNS for subdomains, allowing you to leverage its features without the need to migrate the entire parent domain.
You can either create a new subdomain or migrate an existing one to Route 53, while keeping the parent domain hosted with another DNS service provider.
**Creating a new subdomain with Route 53:**
1. Create a hosted zone for the new subdomain.
1. Add the desired DNS records (e.g., A, CNAME, MX) for the subdomain to the hosted zone.
1. Obtain the Route 53 name servers assigned to the hosted zone.
1. Update the DNS configuration of the parent domain by adding NS (Name Server) records for the subdomain, pointing to the Route 53 name servers.
**Migrating an existing subdomain to Route 53:**
1. Create a hosted zone for the subdomain.
1. Obtain the current DNS configuration for the subdomain from your existing DNS service provider.
1. Add the corresponding DNS records to the hosted zone.
1. Obtain the Route 53 name servers assigned to the hosted zone.
1. Update the DNS configuration of the parent domain by adding NS records for the subdomain, pointing to the Route 53 name servers.
By following these steps, you can leverage Route 53's advanced features, such as health checks, routing policies, and traffic flow management, for your subdomains while maintaining the parent domain's DNS configuration with your existing provider.
**Topics**
+ [
# Creating a subdomain that uses Amazon Route 53 as the DNS service without migrating the parent domain
](CreatingNewSubdomain.md)
+ [
# Migrating DNS service for a subdomain to Amazon Route 53 without migrating the parent domain
](MigratingSubdomain.md)
# Creating a subdomain that uses Amazon Route 53 as the DNS service without migrating the parent domain
You can create a subdomain that uses Amazon Route 53 as the DNS service without migrating the parent domain from another DNS service.
The process has the following basic steps:
1. [Figure out](#decide-procedure-create-subdomain) whether you should even be using this procedure.
1. [Create a Route 53 hosted zone for the subdomain](#CreateZoneNewSubdomain).
1. [Add records](#AddNewSubdomainRecords) for the new subdomain to your Route 53 hosted zone.
1. *API only:* [Confirm that your changes have propagated](#CheckStatusNewSubdomain) to all Route 53 DNS servers.
**Note**
Currently, the only way to verify that changes have propagated is to use the [GetChange](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetChange.html) API action. Changes generally propagate to all Route 53 name servers within 60 seconds.
1. [Update the DNS service for the parent domain by adding name server records for the subdomain](#UpdateDNSParentDomain).
## Deciding which procedures to use for creating a subdomain
The procedures in this topic explain how to perform an uncommon operation. If you're already using Route 53 as the DNS service for your domain and you just want to route traffic for a subdomain, such as www.example.com, to your resources, such as a web server running on an EC2 instance, see [Routing traffic for subdomains](dns-routing-traffic-for-subdomains.md).
Use this procedure *only* if you're using another DNS service for a domain, such as example.com, and you want to start using Route 53 as the DNS service for a new subdomain of that domain, such as www.example.com.
## Creating a hosted zone for the new subdomain
When you want to use Amazon Route 53 as the DNS service for a new subdomain without migrating the parent domain, you start by creating a hosted zone for the subdomain. Route 53 stores information about your subdomain in the hosted zone.
For information about how to create a hosted zone using the Route 53 console, see [Creating a public hosted zone](CreatingHostedZone.md).
## Creating records
You can create records using either the Amazon Route 53 console or the Route 53 API. The records that you create in Route 53 will become the records that DNS uses after you delegate responsibility for the subdomain to Route 53, as explained in [Updating your DNS service with name server records for the subdomain](#UpdateDNSParentDomain), later in the process.
**Important**
Do not create additional name server (NS) or start of authority (SOA) records in the Route 53 hosted zone, and do not delete the existing NS and SOA records.
To create records using the Route 53 console, see [Working with records](rrsets-working-with.md). To create records using the Route 53 API, use `ChangeResourceRecordSets`. For more information, see [ChangeResourceRecordSets](https://docs.aws.amazon.com/Route53/latest/APIReference/API_ChangeResourceRecordSets.html) in the *[Amazon Route 53 API Reference](https://docs.aws.amazon.com/Route53/latest/APIReference/)*.
## Checking the status of your changes (API only)
Creating a new hosted zone and changing records take time to propagate to the Route 53 DNS servers. If you used [ChangeResourceRecordSets](https://docs.aws.amazon.com/Route53/latest/APIReference/API_ChangeResourceRecordSets.html) to create your records, you can use the `GetChange` action to determine whether your changes have propagated. (`ChangeResourceRecordSets` returns a value for `ChangeId`, which you can include in a subsequent `GetChange` request. `ChangeId` is not available if you created the records by using the console.) For more information, see [GET GetChange](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetChange.html) in the *Amazon Route 53 API Reference*.
**Note**
Changes generally propagate to all Route 53 name servers within 60 seconds.
## Updating your DNS service with name server records for the subdomain
After your changes to Amazon Route 53 records have propagated (see [Checking the status of your changes (API only)](#CheckStatusNewSubdomain)), update the DNS service for the parent domain by adding NS records for the subdomain. This is known as delegating responsibility for the subdomain to Route 53. For example, if the parent domain example.com is hosted with another DNS service and you created the subdomain test.example.com in Route 53, you must update the DNS service for example.com with new NS records for test.example.com.
Perform the following procedure.
1. Using the method provided by your DNS service, back up the zone file for the parent domain.
1. In the Route 53 console, get the name servers for your Route 53 hosted zone:
1. Sign in to the AWS Management Console and open the Route 53 console at [https://console.aws.amazon.com/route53/](https://console.aws.amazon.com/route53/).
1. In the navigation pane, click **Hosted zones**.
1. On the **Hosted zones** page, choose the radio button (not the name) for the hosted zone, then choose **View details**.
1. On the details page for the hosted zone, choose **Hosted zone details**.
1. Make note of the four servers listed for **Name servers**.
Alternatively, you can use the `GetHostedZone` action. For more information, see [GetHostedZone](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetHostedZone.html) in the *Amazon Route 53 API Reference*.
1. Using the method provided by the DNS service of the parent domain, add NS records for the subdomain to the zone file for the parent domain. In these NS records, specify the four Route 53 name servers that are associated with the hosted zone that you created in Step 1.
**Important**
Do not add a start of authority (SOA) record to the zone file for the parent domain. Because the subdomain will use Route 53, the DNS service for the parent domain is not the authority for the subdomain.
If your DNS service automatically added an SOA record for the subdomain, delete the record for the subdomain. However, do not delete the SOA record for the parent domain.
# Migrating DNS service for a subdomain to Amazon Route 53 without migrating the parent domain
You can migrate a subdomain to use Amazon Route 53 as the DNS service without migrating the parent domain from another DNS service.
The process has the following basic steps:
1. [Figure out](#decide-procedure-migrate-subdomain) whether you should even be using this procedure.
1. [Create a Route 53 hosted zone for the subdomain](#CreateZoneMigratedSubdomain).
1. [Get the current DNS configuration from the current DNS service provider for the parent domain](#GetParentDomainResourceRecords).
1. [Add records](#AddMigratedSubdomainRecords) for the subdomain to your Route 53 hosted zone.
1. *API only:* [Confirm that your changes have propagated](#MigratingSubdomainCheckStatus) to all Route 53 DNS servers.
**Note**
Currently, the only way to verify that changes have propagated is to use the [GetChange](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetChange.html) API action. Changes generally propagate to all Route 53 name servers within 60 seconds.
1. [Update the DNS configuration with the DNS service provider for the parent domain by adding name server records for the subdomain](#UpdateOldDNS).
## Deciding which procedures to use for creating a subdomain
The procedures in this topic explain how to perform an uncommon operation. If you're already using Route 53 as the DNS service for your domain and you just want to route traffic for a subdomain, such as www.example.com, to your resources, such as a web server running on an EC2 instance, see [Routing traffic for subdomains](dns-routing-traffic-for-subdomains.md).
Use this procedure *only* if you're using another DNS service for a domain, such as example.com, and you want to start using Route 53 as the DNS service for an existing subdomain of that domain, such as www.example.com.
## Creating a hosted zone for the subdomain
If you want to migrate a subdomain from another DNS service to Amazon Route 53 but you don't want to migrate the parent domain, start by creating a hosted zone for the subdomain. Route 53 stores information about your subdomain in the hosted zone.
For information about how to create a hosted zone using the Route 53 console, see [Creating a public hosted zone](CreatingHostedZone.md).
## Getting your current DNS configuration from your DNS service provider
To simplify the process of migrating an existing subdomain to Route 53, get the current DNS configuration for the domain from the DNS service provider that is currently servicing the domain. You can use this information as a basis for configuring Route 53 as the DNS service for the subdomain.
What you ask for and the format that it comes in depends on which company you're currently using as your DNS service provider. Ideally, they'll give you a zone file, which contains information about all of the records in your current configuration. (Records tell DNS how you want traffic to be routed for your domains and subdomains. For example, when someone enters your domain name in a web browser, do you want traffic to be routed to a web server in your data center, to an Amazon EC2 instance, to a CloudFront distribution, or to some other location?) If you can get a zone file from your current DNS service provider, you can edit the zone file to remove the records that you don't want to migrate to Amazon Route 53. Then you can import the remaining records into your Route 53 hosted zone, which greatly simplifies the process. Try asking customer support for your current DNS service provider how to get a *zone file* or a *records list*.
## Creating records
Using the records that you got from your current DNS service provider as a starting point, create corresponding records in the Amazon Route 53 hosted zone that you created for the subdomain. The records that you create in Route 53 will become the records that DNS uses after you delegate responsibility for the subdomain to Route 53, as explained in [Updating your DNS service with name server records for the subdomain](#UpdateOldDNS), later in the process.
**Important**
Do not create additional name server (NS) or start of authority (SOA) records in the Route 53 hosted zone, and do not delete the existing NS and SOA records.
To create records using the Route 53 console, see [Working with records](rrsets-working-with.md). To create records using the Route 53 API, use `ChangeResourceRecordSets`. For more information, see [ChangeResourceRecordSets](https://docs.aws.amazon.com/Route53/latest/APIReference/API_ChangeResourceRecordSets.html) in the *[Amazon Route 53 API Reference](https://docs.aws.amazon.com/Route53/latest/APIReference/)*.
## Checking the status of your changes (API only)
Creating a new hosted zone and changing records take time to propagate to the Route 53 DNS servers. If you used [ChangeResourceRecordSets](https://docs.aws.amazon.com/Route53/latest/APIReference/API_ChangeResourceRecordSets.html) to create your records, you can use the `GetChange` action to determine whether your changes have propagated. (`ChangeResourceRecordSets` returns a value for `ChangeId`, which you can include in a subsequent `GetChange` request. `ChangeId` is not available if you created the records by using the console.) For more information, see [GET GetChange](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetChange.html) in the *Amazon Route 53 API Reference*.
**Note**
Changes generally propagate to all Route 53 name servers within 60 seconds.
## Updating your DNS service with name server records for the subdomain
After your changes to Amazon Route 53 records have propagated (see [Checking the status of your changes (API only)](#MigratingSubdomainCheckStatus)), update the DNS service for the parent domain by adding NS records for the subdomain. This is known as delegating responsibility for the subdomain to Route 53. For example, suppose the parent domain example.com is hosted with another DNS service and you're migrating the subdomain test.example.com to Route 53. You must create a hosted zone for test.example.com and update the DNS service for example.com with the NS records that Route 53 assigned to the new hosted zone for test.example.com.
Perform the following procedure.
1. Using the method provided by your DNS service, back up the zone file for the parent domain.
1. If the previous DNS service provider for the domain has a method to change the TTL settings for their name servers, we recommend that you change the settings to 900 seconds. This limits the time during which client requests will try to resolve domain names using obsolete name servers. If the current TTL is 172800 seconds (two days), which is a common default setting, you still need to wait two days for resolvers and clients to stop caching DNS records using the previous TTL. After the TTL settings expire, you can safely delete the records that are stored at the previous provider and make changes only to Route 53.
1. In the Route 53 console, get the name servers for your Route 53 hosted zone:
1. Sign in to the AWS Management Console and open the Route 53 console at [https://console.aws.amazon.com/route53/](https://console.aws.amazon.com/route53/).
1. In the navigation pane, click **Hosted zones**.
1. On the **Hosted zones** page, choose the radio button (not the name) for the hosted zone, then choose **View details**.
1. On the details page for the hosted zone, choose **Hosted zone details**.
1. Make note of the four servers listed for **Name servers**.
Alternatively, you can use the `GetHostedZone` action. For more information, see [GetHostedZone](https://docs.aws.amazon.com/Route53/latest/APIReference/API_GetHostedZone.html) in the *Amazon Route 53 API Reference*.
1. Using the method provided by the DNS service of the parent domain, add NS records for the subdomain to the zone file for the parent domain. Give the NS records the same name as the subdomain. For the values in the NS records, specify the four Route 53 name servers that are associated with the hosted zone that you created in Step 2. Note that different DNS services use different terminology. You might need to contact technical support for your DNS service to learn how to perform this step.
**Important**
Do not add a start of authority (SOA) record to the zone file for the parent domain. Because the subdomain will use Route 53, the DNS service for the parent domain is not the authority for the subdomain.
If your DNS service automatically added an SOA record for the subdomain, delete the record for the subdomain. However, do not delete the SOA record for the parent domain.
Depending on the TTL settings for the name servers for the parent domain, the propagation of your changes to DNS resolvers can take 48 hours or more. During this period, DNS resolvers may still answer requests with the name servers for the DNS service of the parent domain. In addition, client computers may continue to have the previous name servers for the subdomain in their cache.
1. After the registrar's TTL settings for the domain expire (see Step 2), delete the following records from the zone file for the parent domain:
+ The records that you added to Route 53 as described in [Creating records](#AddMigratedSubdomainRecords).
+ Your DNS service's NS records. When you are finished deleting NS records, the only NS records in the zone file will be the ones that you created in Step 4.