DNS is the address book of the internet. Your domain name means nothing on its own; DNS records tell browsers and mail servers which machine to talk to. If you understand four record types you will understand most of what happens during a launch.
The records that matter
- A record. Points a name to an IPv4 address. Usually your root domain and www point to your web server here.
- CNAME. Points a name at another name. Often used for www or for third party services.
- MX. Tells the world where to deliver email for your domain. Completely independent of your website.
- TXT. Holds verification strings and email authentication records such as SPF, DKIM and DMARC.
Nameservers versus records
Nameservers decide who holds your DNS zone. Records live inside that zone. You either delegate nameservers to us so we manage everything, or you keep your existing DNS provider and we send you the individual records to add. Both work. Delegating is simpler if you want us to handle changes quickly.
Propagation
Changes are not instant. Each record has a TTL, and resolvers around the world hold the old value until it expires. Allow up to twenty four to forty eight hours for a nameserver change, though it is usually much faster. During that window some visitors see the old site and some see the new one. That is normal and not a fault.
Before a migration
Lower the TTL on the affected records a day or two before the switch. That shortens the window considerably. Also record your existing MX and TXT records before changing nameservers, because moving DNS without carrying those across is the classic way to knock out company email during a website launch.
Common mistakes
- Changing nameservers and forgetting MX records. Email dies.
- Multiple SPF TXT records on one domain. Only one is allowed.
- Judging propagation from a browser cache rather than a DNS lookup tool.
Send us your current DNS export before any change. Reply to your email thread or contact [email protected].
