DNS
What is it?
- Domain Name System (DNS)
- The phonebook of the Internet
- A lookup from human readable text to Internet Protocol (IP) addresses
Resource: https://www.cloudflare.com/learning/dns/what-is-dns/


Many kinds of DNS records
- https://en.wikipedia.org/wiki/List_of_DNS_record_types
- Most common / important ones
- A: translates to IPv4 address (e.g. 192.0.2.1)
- AAAA: translates to an IPv6 address (e.g. 2001:0db8:85a3:0000:0000:8a2e:0370:7334)
- CNAME: an alias for another domain (e.g. custom.intercom.help)
- TXT: just text value used for things like authentication
- MX: for setting up email servers (e.g. ASPMX.L.GOOGLE.COM)

Many kinds of DNS records


What makes up a DNS record?
-
Most common parts
- Type
- Host: which subdomain is it active on
- Value: what is the value of the record
- TTL: how long should it should be cached/valid for before asking for the latest value



Layers like an onion

Layers like an onion


Layers like an onion


Layers like an onion


Which DNS server?

- Nameservers
- Configured in domain registrar


How to tell which DNS server?
- MXToolbox is your friend

MXToolBox is a very very good friend

Other tools
- dig


Other tools

Help Centers & HTTPS Custom Domain

- Help Center is hosted on our servers
- Our certificate is only valid for *.intercom.help domains
Help Centers & HTTPS Custom Domain

Help Centers & HTTPS Custom Domain
- Regular CNAME investigations not fully valid for these cases

Help Centers & HTTPS Custom Domain
- Because in this system in the middle between the end user and actual website
- It can handle all requests at the root domain level and have internal configurations to direct the subdomain to the appropriate location without needing a DNS record


Typical problems
- Setting the wrong value
- Using something like `theirdomain.intercom.help` or `intercomworkspacename.intercom.help` instead of `custom.intercom.help`
- Setting up the wrong domain servers
- Not following all instructions in our custom setup
Some examples
1. Why isn't `help.timothyandruth.com` working? See my settings below
2. I set up `docs3.thewheatfield.org`. Why isn't it working?

Set up your own custom help center
- Log into Namecheap via 1Password
- Create your own CNAME and set it up on your own help center
Let's try set up Cloudflare
What could possibly go wrong? 😂
DNS
By Timothy Lim
DNS
- 1,446