Whether you are sending an email or browsing a website, when you input a domain name your computer needs to know how to find the correctserver on the internet. The domain name service (DNS) translates the friendly domain names that we all use into IP addresses that computers need to use to communicate.
This process is completed by a network of DNS resolver servers that cache translations in their databases, if the first DNS resolver doesn’t have the address it will ask another DNS resolver server or the name servers that are set against the domains registration. This is illustrated below:
Now the technical bit!
There are different types of DNS records, the main ones are described below:
A record – This translates a hostname to an IP address
MX record – This tells a sending mail server which host to send mail to for the domain
Once a DNS resolver server uses an address it caches it for a period of time, the time is determined by the time to live (TTL) set on the name servers for the domain. This is usually 24 hours!
Here at Nimbus
We have implemented a three name server infrastructure for domains registered with us, this greatly improves resilience. NS1 and NS2 use one software type and NS3 uses different software for further resilience. Plus, to cover all of the bases, all three name servers are in completely separate data centres. We also set the TTL to just 1 hour by default, this massively improves the time taken for DNS records to be propagated to DNS resolver servers.