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DNS, or Domain Name Service, is the process of taking a name and extension and using them to look up the number of a server. Computers talk in numbers, but names are easier for most humans to remember. DNS provides various resource records that are used to make the Internet work.



If you are using CGI-Communication hosting services (including free parking/redirection), and your domain is registered with CGI-Communication, you should use these name servers:

If you need help with DNS changes, it is recommended that you contact CGI-Communication support rather than experiment on your own. Mistakes in DNS can make your site totally inaccessible or cause some troublesome problems to narrow down.

3rd Party DNS

If your domain is not registered with CGI-Communication (you are using a different provider for your domain), and you are using CGI-Communication for hosting, you are usually required to configure some DNS settings at your domain provider where you registered your domain. You are going to want to make an "A" type redirect. You can find the information required for your domains on CGI-Communication under "Manage Domains" and then "DNS" under the domain you want to redirect from the non-CGI-Communication provider. The type "A" address found there (an IP address) should be copied into the DNS settings of the non-CGI-Communication provider. (The server you are redirecting can be different for each domain, if you have several domains you can not copy paste the information from one domain and be sure it's valid for another.)

Basic DNS Records

Forward mapping of hostname ( to an IP address (
Forward mapping of hostname to an IPv6 address.
Reverse mapping of an IP address ( to a hostname (
Mail eXchange (MX) records tell you which hostname to connect to for sending email.
Say it, See Name, it points one domain name to another domain name, including mail service.
Text records, these are free form text strings, used for things like SPF and DKIM.
Service records advertise a specific service a server offers. VoIP and XMPP Federation (Voice over IP and Google Apps) use SRV records in addition to PTR records.
Delegates a domain or Sub-domain to another DNS server.

Some other details

  • Mail eXchange records consist of two parts, '0', a priority and a domain name. There can be as many MX records as you wish there to be mail servers handling your email. Outgoing email servers connect to the MX servers in order of priority (a lower number means more priority). If two servers have the same priority, it picks one at random. (This in effect load balances the connections)
  • When looking up an A records (like, you can get a CNAME in response (like 'CNAME'). You then lookup the A record of that domain name, and you are either presented with yet another CNAME or an A record.
  • When one cannot control the IP address of their server, such as a home user who receives an IP address from their ISP, Dynamic DNS may be used to keep the domain name properly updated.

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