> ## Documentation Index
> Fetch the complete documentation index at: https://docs.edbb.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Configure Reverse DNS (PTR)

> Set or remove PTR records for your EDBB VPS IPv4/IPv6 directly in the Control Panel.

## Prep Checklist

<Info>
  Reverse DNS works best when the hostname already resolves forward to your VPS.
  Create or update the A/AAAA record first so mail servers and reputation
  services see a matching pair.
</Info>

* 📌 Have the exact FQDN you want to publish (for example `mail.example.com`).
* 🧾 Keep both IPv4 and IPv6 assignments handy—the Network tab lists them.
* 🔒 Plan to use lowercase hostnames without trailing dots; the Control Panel formats PTRs automatically.

***

## Update PTR Records in the Control Panel

<Steps>
  <Step title="Open the rDNS panel">
    Sign in to the <a href="https://my.edbb.com/clientarea.php" target="_blank" rel="noreferrer">EDBB Control Panel</a>, select your VPS under <strong>Services</strong>, and choose the <strong>rDNS</strong> tab.
  </Step>

  <Step title="Set the primary IPv4 hostname">
    Replace the default value with your hostname and click <strong>Set</strong>. Use <strong>Unset</strong> if you need to revert to the system default.
  </Step>

  <Step title="Add IPv6 reverse records">
    For each IPv6 address, enter the suffix (for example <code>:1</code>) and matching hostname, then press <strong>Add</strong>.
  </Step>

  <Step title="Review the summary">
    Confirm the updated entries in the list; edits take effect immediately on EDBB’s side.
  </Step>
</Steps>

<div style={{marginTop: "16px"}}>
  <img src="https://mintcdn.com/edbackboneco/IBH4szipJmqFxhok/assets/setting-up-reverse-pointers.png?fit=max&auto=format&n=IBH4szipJmqFxhok&q=85&s=eb10ec223906a7c97964c7f36b4777b9" alt="Reverse DNS configuration tab with IPv4 and IPv6 PTR fields" style={{width: "100%", maxWidth: "820px", borderRadius: "16px", border: "1px solid rgba(0,0,0,0.08)"}} width="1444" height="666" data-path="assets/setting-up-reverse-pointers.png" />
</div>

***

## Verify - Troubleshoot

* Use `dig -x <ip>` or an external rDNS checker after a few minutes—public caches may need time to refresh.
* If the hostname doesn’t appear, double-check that the forward record exists and matches exactly (including subdomain).
* Still seeing the old PTR? Clear local DNS caches or test from another network.

<Callout type="warning">
  Reverse DNS updates for mail servers should be paired with SPF/DKIM updates.
  Mismatched hostnames can cause outgoing messages to be rejected or flagged as spam.
</Callout>