Frequently Asked Questions — DNS

What is a nameserver?

In their simplest form, nameservers match domain names to IP addresses. When a visitor types a URL into his or her browser, the computer will ask a nameserver for the IP address that corresponds to the domain name he or she specified. Once the visitor's computer has this information, the browser will be able to access the website he or she requested.

You will need nameservers in order to share your server's domain names and IP addresses with the Internet. Without nameservers, potential visitors will be unable to access your server and its websites.

Nameservers also share information with other nameservers, allowing visitors to quickly and efficiently access websites that are hosted by your server. This concept is called propagation. When you first set up a website, its DNS information will take a few days to propagate across the Internet, meaning that potential visitors in some locations will be temporarily unable to access the website.

What's the difference between nameserver software and nameserver records?

• The nameserver software on your server manages nameserver records. cPanel offers 3 nameserver software options: BIND, NSD, and MyDNS.
  • Note: MyDNS nameserver software is only available in cPanel versions 11.32 and later.
• A nameserver record is the resource within a zone file that maps domain names and other services to their corresponding IP addresses. These records also identify which nameservers contain authoritative information about your domains and services.
  • Important: Your server's local zone files must match the domain information you specified to the registrar.

Why do I have to update nameserver records at the registrar?

You must update your nameserver records at the registrar so it can push your domains' DNS information to their top-level domains.

What are the differences between local, private (custom), clustered, and remote nameservers?

• Local — Local nameservers are authoritative nameservers hosted by the same server that hosts corresponding cPanel accounts.
• Clustered — Clustered nameservers are a collection of nameservers that all have authoritative nameserver status for domains and share information amongst themselves. These nameservers are used to prevent down time. If one server fails, then additional servers are available to pick up the slack.
• Private or Custom — This type of nameserver is a custom-branded (vanity) alternative name for the authoritative nameserver.
• Remote — Remote nameservers are authoritative nameservers hosted on a separate server from the website.

What is an authoritative nameserver?

Authoritative nameservers return responses to queries for one or more zones, as opposed to simply caching DNS information for related domains. These types of responses are known as authoritative answers. However, you can configure an authoritative nameserver to return authoritative answers for some zones, while simply caching information for other zones.

What is the difference between clustering and running several nameservers for a domain?

Clustering software ensures that all nameservers in the cluster contain the same information. To run several nameservers on different physical servers, without clustering, you would need to update each nameserver manually whenever a change is made — for example, if a user adds a subdomain. Pointing 2 unclustered nameservers to the same physical server has no purpose.

Do I need to use DNSONLY to cluster?

No, you can cluster several cPanel servers too. You can also configure BIND to cluster with non-cPanel servers; however, we do not support this configuration.

Where are my DNS zone files stored?

On cPanel servers, zone files are stored in /var/named, regardless of the selected nameserver software.

Why is the information about WHM's Nameservers IP feature incorrect?

The functionality of this feature has changed as of cPanel & WHM 11.30.

• For cPanel & WHM 11.30 and later — Nameserver IPs 11.30+
• For older versions of cPanel & WHM — Nameserver IPs before 11.30

Additional Resources

• The Simple DNS Zone File Editor — The simple DNS zone file editor allows cPanel users to edit user-defined CNAME and A records in a zone file.
• The Advanced DNS Zone File Editor — The advanced DNS zone file editor allows cPanel users add and edit user-defined CNAME, A, and TXT records in a zone file. cPanel users can also use this interface to reset all of the information in a specified zone file.
• Adding DNS Zone Files — This WHM feature gives system administrators and resellers the proper privileges for adding new zone files.
• Editing DNS Zone Files — This WHM feature gives system administrators and resellers the proper privileges for editing zone files.
• Editing DNS Zone File Templates — This WHM feature gives system administrators and resellers the proper privileges for changing how zone files are formatted.
• Reverse DNS for BIND — This document explains how to set up and configure reverse DNS (rDNS).
• Editing Records in DNS Zone Files with our XML or JSON API — With the proper permissions, you can use our XML or JSON API to edit DNS zone files.
• Selecting Nameserver Software — This document explains how to change your nameserver software and the differences between available nameserver software.