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Reverse DNS (PTR Records)

Every IP address you own through Get Real IP can have a custom PTR record — the record that maps an IP address back to a hostname. This is what mail servers and other services look up when they want to know “who owns this IP?”

What is a PTR record?

Section titled “What is a PTR record?”

When someone connects to your server, they see your IP address. If they do a reverse DNS lookup on that IP, they get back the PTR record — a hostname you control.

For example, if your IP is 134.49.198.16 and you set a PTR record of mail.example.com, then:

Terminal window
$ dig -x 134.49.198.16
;; ANSWER SECTION:
42.193.49.134.in-addr.arpa.  300  IN  PTR  mail.example.com.

Why does it matter?

Section titled “Why does it matter?”

Mail servers — Running your own mail server (Postfix, Mailcow, etc.)? Most receiving mail servers check for a matching PTR record as part of spam filtering. Without one, your email will likely be rejected or land in spam.

Trust signals — Security tools, firewalls, and network monitoring systems use reverse DNS to identify connections. A proper PTR record helps your traffic look legitimate.

Debugging — PTR records make logs and traceroute output much more readable.

Setting a PTR record

Section titled “Setting a PTR record”

Before you can set a PTR record, you must create a forward DNS A record with your domain’s DNS provider (Cloudflare, Route 53, Namecheap, etc.) pointing your hostname to your static IP. We verify this before accepting the PTR change — if the forward record isn’t in place or hasn’t propagated yet, the update will be rejected.

  1. At your DNS provider, create an A record: mail.yourdomain.com → your static IP (e.g. 134.49.198.16)
  2. Wait a few minutes for it to propagate, then verify: dig mail.yourdomain.com +short
  3. Go to account.getrealip.net
  4. Open your tunnel
  5. Click PTR next to the IP you want to configure
  6. Enter your hostname (e.g. mail.yourdomain.com)
  7. Click Save

Changes propagate within a few minutes. TTL is 5 minutes.

Requirements and best practices

Section titled “Requirements and best practices”

Use a fully qualified domain name (FQDN) — include the full hostname, e.g. mail.yourdomain.com not just mail. A trailing dot is optional.

One PTR per IP — DNS only supports one PTR record per IP address. If you have multiple services on the same IP (running on different ports), pick the most important one — usually the mail hostname if you’re running a mail server.

Clearing a PTR record

Section titled “Clearing a PTR record”

To remove a PTR record:

  1. Open your tunnel in the dashboard
  2. Click PTR on the IP
  3. Clear the hostname field and save

The record is deleted within a few minutes.

PTR records are also automatically deleted when an IP is deactivated or released back to the pool.

IPv6 reverse DNS

Section titled “IPv6 reverse DNS”

Your tunnel also includes a dedicated IPv6 range, and you can set reverse DNS on addresses within it. This matters more than it sounds: IPv6 reverse DNS is something almost no one lets you control. Residential ISPs don’t delegate IPv6 PTR to customers, and even many cloud and VPS providers that offer IPv4 PTR don’t offer it for IPv6. That’s a real deliverability problem now that Gmail and other large receivers expect a valid PTR on the sending IP when mail arrives over IPv6 — a missing IPv6 PTR gets mail junked or rejected. Get Real IP lets you set your own IPv6 PTR records, so your mail server is trusted whether it sends over IPv4 or IPv6.

Because an IPv6 range holds a vast number of addresses (unlike a single IPv4 address), IPv6 reverse DNS is managed a little differently — you can set PTR records for as many specific addresses as you like within your range.

To manage IPv6 PTR records:

  1. At your DNS provider, create a forward AAAA record: host.yourdomain.com → the IPv6 address you want (e.g. 2604:5c00:34:1000:aaaa:bbbb:cccc:dddd). We verify the AAAA resolves to that address before accepting the PTR — set it up first.
  2. Open your tunnel in the dashboard and click PTR on the IPv6 row.
  3. In the dialog, the fixed part of your range is shown (e.g. 2604:5c00:34:1000:); type the rest of the address in the field. It defaults to a suggested address for your range, which you can change.
  4. Enter your hostname and click Add / Update.

The dialog lists your existing IPv6 PTR records so you can add, edit, or delete them individually. Each address you set is validated to fall within your range.

Terminal window
$ dig -x 2604:5c00:34:1000:aaaa:bbbb:cccc:dddd +short
host.yourdomain.com.

The same forward-DNS requirement applies as for IPv4: the hostname’s AAAA record must resolve to the address before the PTR is accepted.

Checking your PTR record

Section titled “Checking your PTR record”

After setting it, verify the record is live:

Terminal window
# Linux/macOS
dig -x 134.49.198.16 +short


# Or using host
host 134.49.198.16


# Or using nslookup
nslookup 134.49.193.x

Online tools: MXToolbox Reverse Lookup, intoDNS