Everyone in the office – including designers and writers – have to know the basics of how the web functions. We stumbled upon this video that greatly simplifies how DNS works. Check it out – the video is courtesy of Lynda.com.
When launching a website you can either change the DNS records at the current name server, or you can change name servers and setup new DNS records. The preferred option is to change DNS records at the current name servers. This usually results in no downtime and takes about 15 minutes to change. One important thing to note is to change the www and the main A record or else the www or non-www version of your website won’t work correctly.
The second option is to change the name servers and transfer the current DNS records, but we recommend this only if absolutely necessary. An instance when it is necessary is if you are no longer using your current web host and the name servers are still pointed to them. If they decide to do an audit, realize that you are no longer a client, delete your website from their servers, your website will go offline.
If you change name servers, you will experience more downtime. Be sure to always transfer prior DNS records including HOST A, CNAME, MX and TXT, if applicable and do not forget to take screenshots of prior DNS records should you want to – or have to – revert back. After the name servers have had time to propagate (meaning the servers have had time to share the updated DNS records), your website will be live.