What is DNS?
If you’re here I’m sure your are wondering “what is DNS?”
Well, all the computers connected to the internet are identified by a unique series of numbers called IP addresses (eg. 94.126.40.154). IP stands for Internet Protocol and these numbers are not easy to remember. Domains were invented because we find it easier to deal with the names, than numbers.
To make it easier to connect specific computers and content, the Domain Name System (DNS) was invented. This is basically an address book which is used to map an easy to remember domain name to an IP address. This then allows any responses sent to the domain name to communicate with the computer that the IP address relates to.
Using DNS is similar to making a phone call with your mobile phone. Your phone dials the number for you and the telephone network uses that number to connect you.
Nameservers
Nameservers form the backbone of the Domain Name System (DNS) as they create the link between a domain name and its email and website services and hold your DNS settings. If you are not using LCN nameservers the DNS settings with LCN will not be used.
For more information on how to update your nameservers can be found here.
Different DNS settings
There are several different settings and records that can be set to your Domain. We have guides on how to add these different types of records here:
How to create an A, AAAA, CNAME or TXT record
How to create or edit an MX record
Below you can find a list of records you can add to your domain and what they will do.
DNS Records
A Records – (Address records) These records are used to link domain names to the IP address of the web server a website is hosted on. If you’ve moved to a new hosting provider, there’s a chance you may need to change or add A records for your domain name.
CNAME Records – (Canonical name records) These records are used to map or point one hostname to another. CNAMEs are commonly used to point one domain name to another domain name; allowing you to display the same website on both domains.
Please Note: CNAME records will supersede an A record. For example, if you have a CNAME and an A record for www.yourdomain.com – the CNAME will resolve and the A record will not.
AAAA records – (so-called Quad-A records) Their primary use, is to link domain names to an IPv6 (IP Version 6) address of the webserver a website is hosted on. If you’ve moved to a new hosting provider, there’s a chance you may need to add AAAA records for your domain name.
MX records – (Mail eXchange records) Their primary use is to direct email sent to your domain name to the correct email server. If you’ve moved to a new hosting provider, there’s a chance you may need to change or add MX records for your domain name.
SPF Records – (Sender Policy Framework) These records specify which mail servers can send email on behalf of your domain. When an email is received, the mail server uses the SPF record to check that mail is being sent by an authorised mail server, if not the mail can be rejected as spam.
If you’re using LCN for your email services, an SPF record is already setup on your domain. If you’re using an external mail provider such as Google Mail you can ask them for an SPF record and add this as a TXT record.
DKIM – (Domain Keys Identified Mail) - records allow you to digitally sign emails from your domain. Recipients of your emails can then verify that the message really did come from your domain and has not been tampered with.
DKIM works by using public and private encryption keys. The private key is used to create encrypted mail headers that are embedded in every email message you send. The public key is added to the DNS records for your domain which allows recipients to retrieve and then use it to decrypt the header and verify the message.
If you run your own mail server and would like to start signing your own emails, dkim.org will give you everything you need.
SRV – (Service records) These records are a general use records that relate to a particular service of the domain e.g. SIP or FTP. They provide flexibility to the DNS system by not having to create lots of new record types for each service. SRV records are popular for newer protocols, for example, Internet telephony (SIP) or Instant Messaging (XMPP) where the desktop programs that connect to the services can find out where it is hosted and additional information such as port and protocol.
One reason for creating an SRV record for your domain would be if you wanted to have a single public SIP address which could be redirected to your current location. If someone wanted to make a SIP phone call to you@domain.com the SRV record on domain.com would tell their SIP program that it should connect to sip.voip-service.com.
That’s it! You now know the different types of DNS records and what they do.