1. Everything You need to know
What is DNS?
Everything You need to know

2. Agenda The Basics DNS Record types Nameservers Accessing & Editing
Helpful resources

3. The Basics DNS stands for “Domain Name System”.
A spreadsheet that controls what a domain does, what website it points to, what service it uses, security, and everything else known about the domain.
Basically the “brain” of the domain name

4. Record types A Record Cname MX Record
Points Domain (example.com) or Subdomain (subdomain.example.com) to an IP address.
Tells the domain where the website is hosted.
Cname
Redirects subdomains to a physical address.
Example: points to example.com
www means “world wide web” and isn’t actually a part of a domain name.
MX Record
“Mail Exchanger”
Used to connect a domain’s inbound, and outbound to a provider.
Aka tells the domain where the goes.
Some providers have separate inbound, and outbound records.

5. Record types TXT SRV SPF Continued
Informational record that displays public information about a domain when requested.
Used by internet services for verification.
Example: Google will ask you to place a TXT record to prove that you own the domain.
SRV
Used to identify locations for specific services.
Example: Allows an FTP program to identify the correct port, and upload server.
SPF
Used for security
Authorizes a specific service to use the domain for to prevent spoofing.
Spoofing = sending out unauthorized s pretending to be you.

6. Nameservers
Nameservers are directors that point services to the DNS zone file in charge of the domain name.
There must be at least 2 nameservers.
One is the primary, and the other is for backup.

7. Accessing & Editing DNS can be edited with your domain registrar.
Except when using custom Nameservers.
Propagation = The time it takes for changes to take effect globally.
Caching = Saving previously used data on closer servers to load content faster.
TTL = “Time to Live” aka how long you want services to cache your dns before rechecking.
They don’t have to listen. Google definitely doesn’t.
Changes can take up to 48 hours to update.
@ = Root domain
Example: Example.com is

8. Resources
Whatsmydns.net = shows how your various records show up globally.
Mxtoolbox.com = Find detailed information about your services.
Senderbase.org = lookup your domain, and online reputation.
developers.google.com/speed/public-dns/cache = Clear Google’s DNS cache to speed up your DNS changes!

9. Let’s Edit some dns!

10. Questions? Leave a comment on the video! Email me at help@1oh1.it
Leave a comment on the compendium!