PTR records, also sometimes called reverse DNS lookup or rDNS, are needed for specific server types like email servers, and other host verification purposes.
It's possible to set up PTR records for IPv4 addresses using DreamCompute. At this time, IPv6 rDNS is not available.
Below details how to configure PTR records.
Step 1: DreamHost panel
You can complete the first step in your DreamHost control panel.
- Navigate to the Manage Domains page.
- If your domain is not yet listed here, click the “Add Hosting to a Domain / Sub-Domain” button near the top left of the page.
- Scroll down to the “DNS Only” hosting section and enter your domain. Click the “Host DNS only!” button. Wait a few minutes for processing.
- Back on the 'Manage Domains' page, click the “DNS” link directly under your domain name.
- In the 'Add a custom DNS record to YOURDOMAIN:' section, enter the A record for the domain or subdomain you wish to host and the PTR record to be based on. For example, if you want “mail.example.com” then “Name” will be “mail”, “Type” will be “A” and “Value” will be your public IPv4 address for your DreamCompute instance. Finally, click Add Record Now!.
Repeat the last step as needed to add additional 'A records' for domains you wish to host on your instance. If you only enter one record, chances are it will pick the right one and get set on its own after a few hours of DNS propagation time. If you add multiple records, the DreamHost system may not pick the one you wanted which requires the last step below.
Step 2: Contact support
Due to the possibly of multiple domains and multiple A records pointing to your public IPv4 address, DreamHost may not pick the one you want by default. To remedy this, please contact support with the following information:
- Which domain or subdomain you want the PTR record to point to.
- The public IPv4 address.
DreamHost support will make sure that your public IPv4 address has the right record set and will push out a DNS update. After waiting 4 or so hours for DNS propagation, your PTR record should show.
Step 3: Checking PTR Records
Allow at least four hours for DNS propagation. After this you can check for the proper value. To do so from the command line, run the following:
[user@localhost]$ dig -x PUBLICIPADDRESSHERE