How do I setup rDNS for my IP address(s)?

You set up rDNS by adding a PTR record for your IP. If you see an rDNS option for your VPS in Virtualizor, add it there. If you do not see that option, open a support ticket and we will set it for you.

Before you start

• Decide the exact hostname you want each IP to map to, and create matching A or AAAA records that point back to the same IP. Add those records wherever the domain's zone is actually hosted. If the domain uses Hostworld nameservers (ns1.serverworld.uk, ns2.serverworld.uk, ns3.serverworld.uk, ns4.serverworld.uk) and you also hold a Hostworld web hosting account, that will be cPanel's Zone Editor. If your VPS is your only service with us, the zone is elsewhere: add it there, and if you are not sure where, open a support ticket and ask.
• Have the exact IPv4 and IPv6 addresses ready.
• If the IP sends mail, plan to align your server hostname and SMTP HELO with the PTR once it is set.

Step 1: Set the PTR in Virtualizor or request it from us

Virtualizor on a Hostworld VPS

If rDNS management is available for your VPS, you can set it in Virtualizor. Open your VPS from the Hostworld client area and set the hostname you prepared against each IP, then save.

If you see “RDNS Zone entry not found. Please contact the Administrator.”, or there is no reverse DNS option at all, the reverse zone is not delegated to end users. Go to the next section.

Ask Hostworld to set it

Open a support ticket and include:

• Your service reference or VPS name.
• The exact IPv4 and/or IPv6 address(es).
• The exact hostname you want each IP to resolve to.

We will add the PTR. If the hostname does not already resolve back to the same IP, we will ask you to create or correct the A/AAAA first.

Step 2: Verify the change

Run a reverse lookup. These commands show the current PTR that resolvers see.

dig -x 203.0.113.10 +short
host 203.0.113.10

dig -x 2001:db8::123 +short
host 2001:db8::123

Also check forward-confirmed rDNS. The PTR target must resolve forward to the same IP. You can use an online FCrDNS checker, or repeat dig/host on the PTR target and confirm the A/AAAA matches your IP. A resolver will keep serving the previous answer until the record's TTL expires, so check the TTL shown in the lookup, then test again after it has passed or from a network that has not cached the old value.

Step 3: Align mail identity if this IP sends email

Make sure the hostname in your PTR matches the hostname your mail daemon presents in HELO/EHLO, and that the same hostname resolves forward to the same IP. If the three do not agree, receiving servers can treat the mail as suspect even though the PTR exists.

If it does not work

• No rDNS option or “RDNS Zone entry not found” in Virtualizor: the reverse zone is not delegated. Open a support ticket with the IPs and hostnames and we will add the PTRs.
• PTR shows but FCrDNS fails: the hostname in the PTR does not resolve back to the IP. Create or correct the A/AAAA, wait for the cached answer to expire, then test again.
• Deliverability warnings or HELO mismatch: use one PTR per IP, remove any trailing spaces in custom HELO settings, and make the server's HELO match the PTR target hostname.

What next

For a wider explanation of PTR, forward DNS and FCrDNS, see our VPS guides. Operating system options for new builds are listed on our UK VPS page. If you need us to review your rDNS change, open a support ticket.