If you've ever had your website suddenly vanish from the internet, load painfully slow, or redirect visitors to a mysterious error page, there's a good chance the culprit is a DNS misconfiguration. DNS—short for Domain Name System—is like the internet’s address book. If it’s set up wrong, nothing finds its way home.

The good news? DNS is totally fixable. Even better news? Once you know what to look for, you can prevent most issues from happening in the first place.

What We’ll Cover

  • What DNS actually does (and why it matters)
  • 7 common DNS mistakes that can crash your website
  • How to fix each one (in human-friendly steps)
  • Ongoing tips to keep your DNS clean and secure

What Is DNS, Really?

DNS, or Domain Name System, is like your website’s GPS. It translates your domain name (like yourbrand.ca) into an IP address that browsers can understand. If the DNS record is wrong, your visitors don’t reach your website—they hit a dead end. Every domain uses DNS, so understanding how it works is crucial for anyone running a business online.

1. Forgetting to Update DNS After Moving Hosting

The mistake: You’ve upgraded your hosting provider (good call), but your DNS still points to the old IP address. Your site either shows outdated content or breaks completely.

The fix:
Update your A record with the new IP address from your hosting provider. You’ll find this in your domain’s DNS settings—usually within your domain registrar account, unless you are using name servers to point to a different provider. This tells browsers where to find your site’s new home.

2. Not Setting a TTL That Makes Sense

The mistake: TTL (Time to Live) determines how long DNS records are cached before refreshing. If it's too high, your site updates or migrations take forever to reflect. Too low? Your DNS may get hammered with unnecessary requests.

The fix:
Most providers have a default TTL, it's usually best to keep it this way. If there is no default, set your TTL to around 1–4 hours for stability. Before major changes like a site migration, lower it to 5 minutes (300 seconds) for flexibility. Once everything is stable, increase it again to reduce server load.

3. Missing or Incorrect MX Records for Email

The mistake: Emails bounce back, get lost, or just don’t work—and it's often due to missing or incorrect MX (Mail Exchange) records.

The fix:
Add the correct MX records based on your email provider’s exact instructions. If you’re using something like Rebel Cloud Email, make sure your domain points to their mail servers. Also, it's important to configure SPF, DKIM, and DMARC records for better deliverability and email security.

4. Mixing Up CNAME and A Records

The mistake: Using a CNAME for your root domain (like yourdomain.ca) instead of an A record. This causes your domain to break entirely, because root domains aren't allowed to be CNAMEs. This can take down your website and emails.

The fix:
Always use an A record for your root domain, and reserve CNAME records for subdomains like www or blog. Think of A records as direct street addresses, and CNAMEs as clever shortcuts that only work in the right context.

5. Conflicting DNS Records

The mistake: You have multiple records for the same subdomain or service type—like two A records or two MX records with different priorities—and they’re not coordinated. This confuses DNS resolvers, and the results can be unpredictable.

The fix:
Clean up redundant or contradictory entries. Only include one A record per subdomain (unless you’re intentionally load balancing), and make sure MX records are prioritized correctly. Use your DNS management tool to review all active records and eliminate overlaps.

6. Formatting Errors in DNS Records

The mistake: One small typo in a record—an extra period, wrong spacing, incorrect hostname format—and your entire DNS configuration can break.

The fix:
Follow the formatting rules exactly. For example, don’t add a trailing period on a domain unless it’s explicitly required. Double-check IP addresses, subdomain syntax, and TXT records for email. In these cases, copy-paste will be your best friend whenever your provider gives your DNS information.

7. Letting Your Domain Expire

The mistake: Your domain name wasn’t renewed in time. Everything—your site, email, and branding—goes offline until it’s recovered (and that’s if no one else grabs it).

The fix:
Enable auto-renewal on your domain and keep your payment details up to date. Even better? Use Rebel’s expiry protection in case of forgetting, we will renew your domain for you to ensure your online presence is safe.

How to Keep DNS from Derailing Your Website

DNS isn’t just a tech detail—it’s foundational to your site’s performance, reliability, and trust. Make a habit of:

Reviewing DNS settings after major changes

Using a reliable registrar

Backing up your DNS zone files

Testing changes with DNS tools before pushing them live

It’s worth it. You’ll avoid the most frustrating kind of downtime—the kind that’s totally preventable.

Ready to take control of your domain and avoid all the DNS drama? At Rebel.com, you can register your domain with confidence—and know that real, human support is always just a click or call away. Whether you're launching a new site or cleaning up old DNS records, our friendly team is here to guide you step-by-step. Because the only thing better than a powerful domain is peace of mind that comes with it.