Records 101
A crash course to get you learning the crucial parts of a domain's DNS.
A crash course to get you learning the crucial parts of a domain's DNS.
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There is usually a lot of confusion about what each DNS record will do. Or how are they supposed to help you. This lesson was designed to better explain how to properly configure your domain to work properly. Topics covered in this lesson:
For some basic sample configurations that our users ask us please click here. Each of these records map a name to an IP address. Example:
NOTE: It is important to know that only an A record can be made for your root host record. If you have a domain called example.com. and if you want an IP for example.com. then A record is the only valid solution for this. CNAME records are invalid. DNS Made Easy also supports Wildcard records. Click here to learn more about what these are. Wildcard Records give you the ability to map all (or a section) of the records in your domain to one IP. All Wildcard records are created with A records. If you create a record that is part of your domain (and inclusive of the wild card set) then only that record is directed to the other IP and everything else will goto the Wildcard record. Example:
The 'www' record would goto 10.2.54.4 but all of the other IPs would goto 192.168.1.2 All members can create Wildcard records for their domains. Load balancing / Round Robin allows you to distribute your server load evenly among multiple servers. This can all be handled in DNS Made Easy so you do not need to purchase expensive load balancers. The best part is that this service is "free" for all DNS Made Easy users! All you have to do is create multiple A records with the same name but with a different IP / value. Example:
50% of the time a user would go to 192.168.1.2 and 50% of the time the users would go to 10.2.54.4. You can even split the traffic to more hosts. For example:
NOTE: There is generally a limit of (thirteen) 13 hosts that you can round robined (13 A records with the same name and different values) due to the limitations of the UDP packet which is what the DNS protocol generally runs over. You can even combine this service with our DNS Failover service to remove a server from the loop if it is down! CNAME Record (Canonical Name Record) These are usually referred to as alias records since they usually map an alias to its canonical name. The name server does handle these queries differently from an A record. When a name server looks up a name and finds a CNAME record, it replaces the name with the canonical name and looks up the new name. This allows you to point multiple systems to one IP without specifically assigning an A record to each host name. If your IP was ever to change you would only have to change one A record. Example:
When the DNS server is queried for the ftp.dnsmadeeasy.com. system it realizes that it is an alias for www.dnsmadeeasy.com.. The system then returns the value of www.dnsmadeeasy.com.. which is 192.168.1.2. Whatever www.dnsmadeeasy.com. points to then so does ftp.dnsmadeeasy.com.. You can also use CNAME to point a record in one zone to a record in another zone. The following is valid:
NOTE: It is important that CNAME always are to the left hand side. You should never make an alias to an alias. Or you should never use MX or NS records with CNAME records. You can read more about NS and MX records later in this document. NOTE: It is important to know that only an A record can be made for your root host record. If you have a domain called example.com. and if you want an IP for example.com. then A record is the only valid solution for this. CNAME records are invalid. NS Record (Name Server Record) These records indicate which name servers are authoritative for the zone. Example:
You can also use NS records to assign the authoritative name server for a subdomain. Example:
Name servers will query ns1.dnsmadeeasy.com. for records in the sub.dnsmadeeasy.com. sub-domain MX Record (Mail Exchange Record) These records tell mail servers where to deliver mail. The name field of an MX record contains the host name which appears in the e-mail address, and the data field contains the hostname of the server to which the mail should be delivered. Two MX records that define the mail servers for the dnsmadeeasy.com domain might contain the following:
You can read all about the Redirection Service product here. These are special records in that they are a combination of an A record and the use of an application server. There will be an A record pointing to our application servers which will redirect to the URL you specify. HTTP Redirection Records allow you to map your FQDN to any URL of your choice. All users can create HTTP Redirection Records with any DNS Made Easy domains (our domains that you can use for free). The ability to create HTTP Redirection Records for your own domain is a special service that can be purchased seperately or is already included in the Premium Membership.
These records are simply a list of strings, each less than 256 characters in length. TXT records can be used for anything you want. Example Input for
Domain Name: example.com Result:
Pointer records are used to map a network interface (IP) to a host name. These are primarily used for reverse DNS. Example Input
for Domain Name: 1.168.192.in-addr.arpa Result: Of course 192.168.1.x is an internal network and would not be allowed in the DNS Made Easy system.
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