Complete Guide to DNS Records: A, CNAME, MX, TXT Explained

DNS (Domain Name System) records are the instructions that tell the internet how to find and connect to your website, email server, and other online services. Understanding DNS records is essential for managing your domain effectively, troubleshooting connectivity issues, and configuring third-party services. This guide explains every major DNS record type you will encounter as a SakuraHost user.

How DNS Works: A Quick Overview

When someone types your domain name (e.g., yourdomain.co.tz) into their browser, their computer queries DNS servers to find the IP address associated with that domain. This process is called DNS resolution. The DNS servers consult your domain's zone file, which contains various records that map domain names to IP addresses, mail servers, and other destinations.

Think of DNS as the internet's phone book. Your domain name is the contact name, and the DNS records are the phone numbers and addresses associated with that name.

A Record (Address Record)

The A record is the most fundamental DNS record. It maps a domain name to an IPv4 address, telling browsers which server hosts your website.

You can have multiple A records for the same domain (for load balancing or failover). The Name field can be the root domain (@) or a subdomain (blog for blog.yourdomain.co.tz). The Value is always an IPv4 address in dotted decimal format.

AAAA Record (IPv6 Address Record)

The AAAA record is the IPv6 equivalent of the A record. It maps a domain name to an IPv6 address. As IPv6 adoption grows, having AAAA records ensures your website is accessible to visitors using IPv6 connectivity.

CNAME Record (Canonical Name Record)

A CNAME record creates an alias that points one domain name to another domain name (not an IP address). This is commonly used for subdomains and third-party service integrations.

In this example, www.yourdomain.co.tz points to yourdomain.co.tz, which in turn resolves via its A record to the server's IP address. Common uses for CNAME records include:

• Pointing www to the root domain
• Configuring custom domains for services like Google Workspace verification, Shopify, or Mailchimp landing pages
• Setting up subdomains for CDN services like Cloudflare

MX Record (Mail Exchange Record)

MX records specify which mail servers are responsible for receiving email for your domain. Without correctly configured MX records, email sent to your domain will not be delivered.

The Priority value (also called preference) determines the order in which mail servers are tried. Lower numbers have higher priority. If you have multiple MX records, email is delivered to the lowest-priority server first, with higher-priority servers serving as fallbacks.

If you use external email services, you will need to replace the default MX records with those provided by your email provider:

TXT Record (Text Record)

TXT records store arbitrary text data associated with your domain. They serve many purposes in modern DNS, with the most important being email authentication and domain verification.

SPF (Sender Policy Framework)

SPF records specify which servers are authorized to send email on behalf of your domain. This helps prevent email spoofing and improves email deliverability.

This SPF record authorizes the server at the A record, the MX server, and the specific IP address to send email for the domain. The ~all softfails all other senders.

DKIM (DomainKeys Identified Mail)

DKIM adds a digital signature to outgoing emails, allowing receiving servers to verify the email was genuinely sent from your domain and was not tampered with in transit. DKIM records are TXT records with a specific naming format:

DMARC (Domain-based Message Authentication)

DMARC builds on SPF and DKIM to provide policy instructions for handling emails that fail authentication checks.

Domain Verification

Many third-party services (Google Search Console, Microsoft 365, Facebook Business) require you to add a TXT record to verify domain ownership.

SRV Record (Service Record)

SRV records define the location (hostname and port) of specific services. They are used by protocols like SIP, XMPP, and Microsoft 365 services (Skype for Business, Teams).

CAA Record (Certification Authority Authorization)

CAA records specify which certificate authorities are allowed to issue SSL certificates for your domain. This provides an additional layer of security against unauthorized certificate issuance.

TTL (Time to Live)

Every DNS record has a TTL value measured in seconds. TTL controls how long DNS resolvers cache the record before checking for updates. Common TTL values are 300 (5 minutes), 3600 (1 hour), and 14400 (4 hours). Lower TTLs mean changes propagate faster but generate more DNS queries. For more about how DNS changes propagate, see our article on Understanding DNS Propagation and Why Changes Take Time.

For comprehensive DNS documentation, visit Cloudflare's DNS Learning Center or the cPanel Zone Editor documentation. For assistance managing your DNS records, contact SakuraHost support at billing.sakurahost.co.tz.