DNS

DNS, or Domain Name Service, provides various records that are looked up and used to make the internet work.

DreamHost DNS

 * You can review all of the DNS that is setup for any site you host at DreamHost by clicking on the DNS link next to a domain on the Manage Domains page. This information is very handy if your domain points to non-DreamHost name servers and you need to setup any or all of these records manually to point to DreamHost hosted services.

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

You can also create Custom DNS entries on that page, but you should only do so if you know what you are doing. For instance, it is often recommended that you create an SPF record to make it harder for spammers to send email that pretends to come from your domain.

There are numerous records that you cannot edit on that page. If you need to modify the A record for the domain, "www", or "ftp" you will need to remove the web hosting from that domain to do so. NOTE: When you remove the web hosting, it will take some time before the change is reflected in the DNS records. You can force the refresh, but you can only force a refresh once every 12 hours.

If you need help with this or any other DNS changes it is recommended that you contact DreamHost support rather than experiment. Mistakes in DNS can make your site totally inaccessible.

For more instructions, see the article Custom DNS

Non-DreamHost DNS
If your domain is not registered with DreamHost (you are using a different provider for your domain), and you are using DreamHost 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 DreamHost under "Manage Domains" and then "DNS" under the domain you want to redirect from the non-DreamHost provider. The type "A" address found there (an IP address) should be copied into the DNS settings of the non-DreamHost 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
See also Custom DNS
 * A : Forward mapping of hostname (dreamhost.com) to an IP address (208.113.157.108).
 * AAAA : Forward mapping of hostname to an IPv6 address.
 * PTR : Reverse mapping of an IP address (e.g, 208.113.157.108) to a hostname (dreamhost.com).
 * MX : Mail eXchange records tell you which hostname to connect to for sending email.
 * CNAME : Say it, See Name, it points one domain name to another domain name, including mail service.
 * TXT : Text records, these are free form text strings, used for things like SPF.
 * SRV : Service records advertise a specific service a server offers. Some applications such as Zeroconf and XMPP Federation (Jabber and Google Apps) use SRV records.
 * NS : Delegates a domain or subdomain to another DNS server.

Some other details

 * Mail eXchange records consist of two parts, '0 mail.domain.com', 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 dreamhost.com), you can get a CNAME in response (like 'CNAME somewhere.com'). 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.