A Primer on DNS and QUIC.cloud

QUIC.cloud requires that you change the DNS configurations for your site to a value provided by QUIC.cloud. This is required to serve your site globally.

DNS is a tricky system. This primer will answer any/all questions regarding the DNS and how it impacts you and QUIC.cloud.

1. Domains and IP Addresses

A domain is what you named your site. example.com, example.net; whatever it may be, it is yours and you got it from a Domain Name Registrar. This is also known as the apex domain. A sub domain is a prefix to your domain. A period separates the sub portion from the domain. E.g. sub.example.com, www.example.com are both sub domains. In most cases, you only purchase a domain name and you are free to create as many sub domains as you wish.

Your site exists on a server. Somewhere in the world, there is a server that contains the code for your site that is publicly accessible by an IP address. Publicly accessible means that anyone in the world with an internet connection can reach that server. An IP address is an address defined by the Internet Protocol. There are two types of IP addresses, IPv4 and IPv6. For the primer, we will only discuss IPv4 addresses because it is the type used in a vast majority of situations.

IPv4 stands for Internet Protocol version 4. This boils down to four numbers, ranging 0 - 255, separated by periods, '.'. Internet providers assign an IP Address to each machine to make it publicly accessible. This is possible because public IP Addresses are unique.

The DNS (Domain Name System) is the system that matches domains to IP addresses. A DNS record is a configuration that instructs browsers on what to do when someone requests your site. Every time someone visits your site via a browser, it looks up the domain in the DNS to find the IP of your server. From there, the browser will visit the server's IP to fetch your site. Most likely, when you purchased your domain name, the registrar provided a place for you to create DNS Records.

2. DNS Records

Simply put, a DNS record is a configuration entry that specifies how browsers should handle a domain.

Every DNS record includes a TTL (Time To Live) setting. This is a timeout in seconds - when a DNS recursor retrieves a record, it will save the record for that period of time. Once the TTL expires, the DNS recursor needs to retrieve the record again.

There are many types of DNS records, but we will only cover the NS, A, AAAA, CNAME, and MX records; these are the records that have major significance for configuring QUIC.cloud.

The NS record specifies the Name Server for your domain; that is, which DNS service provider you want managing your DNS. For example, you could specify Google, Digital Ocean, CloudFlare, etc. in the NS record. Then only the records that come from that service provider's servers are to be followed by the rest of the DNS servers. A Name Server from Digital Ocean, for example, looks like ns1.digitalocean.com.

The A record pairs your domain to an IP address.

The AAAA record is identical to an A record, except it is used for IPv6 addresses. From here on, all mentions of A record apply to the AAAA record as well.

The CNAME record is meant to be used for aliases. This is useful if you have sub domains that are hosted on the same machine. In almost every situation, this is the case. CNAME records pair a domain to another domain.

The Rules of DNS implicitly requires that you assign your apex domain with an A record. The reasoning boils down to: the NS server must contain a record for the domain and a CNAME record may not exist on the NS server. Therefore, in order to configure the apex domain on the NS server (thus, discoverable by the DNS), it must use an A record.

The MX record indicates the mailserver used by the domain. If you manage your own mailserver, the MX record indicates the domain of the mailserver (e.g. mail.example.com) and the priority of this mailserver. A lower value associated with the mailserver indicates higher priority.

3. How this Applies to QUIC.cloud

At present, QUIC.cloud uses AWS's Route53 as its DNS. QUIC.cloud generates a sub domain for you to use with your site. We ask that you change/create a CNAME record that points your domain/subdomain to the one provided in your client area. With this, you are able to use our POPs.

Given that DNS forbids using CNAME for an apex domain, we ask that you use the www. sub domain as the primary accessor for your site. Since www. is a sub domain, you are permitted to use a CNAME record with it.

4. Workarounds

A few DNS managers, such as CloudFlare, provide a way to use aliasing records for your apex domain. If you wish to use the apex domain with QUIC.cloud as well, we recommend that you try one of these providers.