> For the complete documentation index, see [llms.txt](https://docs.glesys.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.glesys.com/products/connectivity/ip-addresses/how-tos/change-ptr-records.md).

# Change PTR records

PTR records are used to reverse lookup; that is, to lookup a hostname for an IP address.

***

## Change a PTR record using the control panel

PTR records are used for reverse DNS lookups. Instead of resolving a name to an IP address, a PTR record resolves an IP address to a name.

These PTR records can be modified under **IP addresses** in the control panel. On the **Overview** tab, you can see all your IP addresses, both reserved and those in use on a server.

To change the PTR record, click the pencil icon to the right of the IP address.

<figure><img src="https://3379166260-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FlMZhhdQNcWOpX5Bj48GK%2Fuploads%2FckYGOGYalhZyTSeQKdiU%2Fedit-an-ip-address-ptr-pointer.png?alt=media&amp;token=214e01e8-bfa8-4de4-95a1-b4fc273d7a13" alt=""><figcaption></figcaption></figure>

A dialog box will open where you can enter the new FQDN (fully qualified domain name) for the IP address. Note that the name must end with a period. The period indicates the top of the DNS hierarchy.

Once you have entered the new name, click **Update**.

<div align="left"><figure><img src="https://3379166260-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FlMZhhdQNcWOpX5Bj48GK%2Fuploads%2FJgMc8gCxKzkdcykTiaGj%2Fchange-the-ptr-pointer.png?alt=media&amp;token=15642374-6430-4ead-8451-8e8516313034" alt=""><figcaption></figcaption></figure></div>

You can now test whether the IP address points to the correct name using the `host` command:

{% code title="Command" %}

```
host 203.0.113.49
```

{% endcode %}

{% code title="Output" %}

```
49.113.0.203.in-addr.arpa domain name pointer labserver1.glesys.com.
```

{% endcode %}

## Change a PTR record using the API

1. To check the current PTR record for an IP address using the [API](/platform/control-panel/api.md), use the [ip/details](https://github.com/GleSYS/API-docs/wiki/API-Documentation#ipdetails) endpoint.
2. To change the PTR record for an IP address, use the [ip/setptr](https://github.com/GleSYS/API-docs/wiki/API-Documentation#ipsetptr) endpoint.