Workshop Clip: DNS

Clip from my session on DNS during day one of Reclaim’s Administrator Workshop. During the 45-min talk, we covered DNS basics, types of DNS records and how to edit them, handy DNS tools & strategies, and frequently asked questions.

If you missed the workshop clip on Supporting DoOO, you can find that here.

Documentation guides that I wrote for this talk are linked below:

DNS Full Category
DNS Summary
Handy DNS Tools
DNS Frequently Asked Questions
Editing DNS Records in cPanel
Editing DNS Records in WHM

DNS Intro

Humans are better with names than they are with numbers. If I want to visit a specific website on the internet, I’d rather remember the domain name attached to the site (reclaimhosting.com) as opposed to the IP address of the server where the site lives (162.243.224.94).

However, computers are better with numbers, not names. So we have to find something that translates domains to IP addresses and vice versa. We do this with DNS, which stands for Domain Name System. Just as it sounds, DNS is a protocol for names of systems.

So when I type reclaimhosting.com into my web browser, I’m asking a resolver, or query participant, to send out a DNS query. What exactly is a DNS query? Well, it could look like one of two things:

•A recursive query asks the DNS server, “Can you look for the IP for me and report back?”
•An iterative query says, “if you can’t find it, send along the next place I should look. I’ll keep looking until I find an answer.”

Once the end DNS server receives the query, it sends a “hey, I’m over at this IP address!” message back to my browser. At that point, the translation is over and the browser communicates using just IP addresses from that point on.

DNS works by holding individual records. Records are simply single mappings of between a domain location and a server. (If we’re using the “your domain is your house” metaphor, a record would be a single direction to get to your house.) While there are dozens of record types, some are way more common than others. Here are the most common DNS records that you may deal with in a Domain of One’s Own instance:

A Record: This is your pointer record– kind of like speed dial for a host. It’s the most common DNS record and is used to point a domain/subdomain to an IPv.4 address.

AAAA Record (“Quad-A Record”): This is essentially an updated version of the A record built primarily for the IPv.6 address. So an A record is hardly wrong, but if both the A record and the AAAA record exist, the network will prefer the AAAA record.

CNAME Record: (Canonical Name) This record allows you to refer to a location by more than one name. A CNAME is used to map an alias to a domain name. Ex: mapping the subdomain ‘www.’ to the domain it’s associated with.

MX Record: (Mail Exchange/Mail Exchanger)- The MX record is built to identify mail services; it specifies what server is responsible for handling email associated with the domain name. If there are multiple mail servers available, you can prioritize your records.

NS Record: (Nameserver) Helps identify other nameservers in the DNS hierarchy.

TXT Record: Just that- a text record is used to store additional information.

An in-depth overview of DNS Concepts, terminology, etc can be found here.

Handy DNS Tools

DNS, in general, has always been an intimidating topic for me. But the more you practice and work with it, the easier it gets! The following list of tools helps make my life easier when changing records, troubleshooting errors, etc.

What’sMyDNS

Going to What’sMyDNS.com is super useful if you want to check the status of DNS records during a move. If you’re pointing your domain to a different hosting service, for example, or routing your domain’s email through Gmail, you’ll have to edit nameservers or MX records, respectively. Whenever you make changes to DNS records, a good rule of thumb is that it takes up to 24-48 hours for those changes to stick. So staying on top of where everything is pointed can be really helpful in understanding a website error or DNS delay.

Simply search the domain in question and use the menu drop-down to change the record that you’re interested in:

 

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