A comprehensive domain monitoring and troubleshooting guide

Many website owners spend time picking the right domain name and setting it up, but then forget one key part: keeping an eye on it. Domain monitoring is often ignored, even though it plays a big role in website stability, security, and uptime.

If your domain expires, or you run into DNS issues, your entire site can go down without any warning. That’s why regular domain monitoring needs to be an integral part of your website management.

This guide walks you through what domain monitoring is, why it matters, and how to troubleshoot common domain-related problems. Let’s get to it!

The basics of domain monitoring

Domain monitoring is all about keeping track of key details related to your domain name so you can catch and resolve any problems in a timely manner. Here are its core elements:

• Expiration tracking: Making sure your domain doesn’t expire by mistake.
• DNS monitoring: Watching for unexpected changes to DNS records like A, MX, CNAME, or NS.
• SSL certificate status: Ensuring that your SSL certificates are valid and aren’t nearing expiry.
• Blacklist monitoring: Checking if your domain has been flagged on spam or malware lists.
• Name server health: Verifying that your domain’s name servers are reachable and working.
• WHOIS changes: Making sure ownership and registrar details are accurate and haven’t been tampered with.

Why is active domain monitoring important?

Domains are exposed to a lot of risks, and without active monitoring, you may not notice something’s wrong until your site goes offline. Here are some reasons why all website owners need domain monitoring:

Preventing accidental expiry

When a domain expires, your website and email services can stop working immediately. In some cases, the domain may even become available for others to register. This can lead to a major disruption, especially if the domain is tied to your business or brand. Active monitoring ensures you get timely alerts well before the expiration date, so you have enough time to renew and avoid any service interruptions.

Detecting DNS tampering or misconfigurations

DNS records control how users and systems find your website and other linked services. If someone makes unauthorized changes or if a record is misconfigured, it can cause website outages, or even redirect users to malicious sites. Without monitoring, these issues can go unnoticed for hours or days. DNS monitoring helps catch any changes early so you can fix problems before they affect users.

Staying on top of SSL certificate expiry

SSL certificates help keep data secure and signal to your visitors that your site can be trusted. If a certificate expires, browsers will show a security warning, which can scare users away and damage your reputation. In some cases, certain features or payment gateways might also stop working. Monitoring your SSL status helps you renew certificates on time and avoid these issues.

Protecting against domain hijacking

WHOIS information includes important details about domain ownership and registrar settings. If this data is changed without your knowledge (e.g., due to hacking or an internal error), you could lose control of your domain. Hijackers may transfer the domain elsewhere or redirect traffic for malicious use. Monitoring WHOIS records helps you catch unauthorized changes before they turn into bigger problems.

Catching blacklisting issues early

Domains can end up on blacklists if they’re linked to spam, malware, phishing, or even outdated software. When that happens, emails from your domain may get blocked, and users might see warnings when trying to access your site. Regular blacklist checks let you act fast, remove malicious content if needed, and request removal from the blacklists.

Ensuring name server availability

Your domain’s name servers connect your users to your site. If they go down or become unreachable, your domain will stop resolving, and your website and email will go offline. This kind of issue is easy to miss without proper monitoring.

What to monitor and how

Now that you know just how important domain monitoring is, let’s discuss the specific metrics and items you should monitor regularly:

• Domain expiration date: Track when your domain is set to expire. Renew it before the deadline to avoid losing access or having someone else register it.
• Registrar lock status: Make sure your domain remains locked to prevent unauthorized transfers.
• WHOIS contact details: Monitor admin, technical, and registrant contact info. Any unexpected changes could be signs of tampering or hijacking attempts.
• Name server records (NS): Keep an eye on the NS records configured for your domain.
• A record (IPv4 address): Confirms that your domain points to the correct server IP. A wrong value can break your site.
• AAAA record (IPv6 address): Like the A record, but for IPv6. Useful if your site supports both IPv4 and IPv6.
• MX records: These control email delivery. Any incorrect or unauthorized changes here can result in lost or delayed emails.
• CNAME records: These are used for aliasing one domain to another. Changes can cause misrouting or service disruptions.
• TXT records (especially SPF, DKIM, DMARC): These are critical for email authentication. Changes or errors here can cause email spoofing or cause your emails to go to spam.
• SSL certificate expiration: Always track certificate validity and renewal dates to avoid browser warnings or broken HTTPS.
• SSL certificate issuer and subject details: Check for unauthorized or unexpected certificates issued for your domain.
• Certificate revocation status: Verify that your SSL certificate hasn’t been revoked, which could break secure access.
• HTTP/HTTPS response time: Monitor how quickly your domain responds to requests. Sluggish responses can point to server or DNS issues.
• HTTP status codes (like 200, 301, 404, 503): These help you track whether your site is loading correctly or not.
• Blacklist status (Spamhaus, SURBL, Google Safe Browsing, etc.): Check if your domain is listed on any security or spam blacklists.
• DNS resolution time: Measures how quickly DNS queries for your domain are answered. High latency could signal issues with your DNS provider.
• Propagation status: When making DNS changes, check that updates are propagating correctly across global DNS servers.
• DNSSEC status: Monitor whether DNSSEC is enabled and working as expected to help prevent DNS spoofing.
• Zone file integrity: Ensure your DNS zone files haven’t been altered in ways that could affect service.
• Uptime monitoring: Keep track of whether your website has crashed or restarted over time.
• Content checks: Verify that the content served on your site hasn’t been changed, or injected with malicious scripts.
• Uptime monitoring: Keep track of whether your website has experienced any downtime or unexpected restarts.

To track all this effectively, you should ideally use a website monitoring tool that also supports domain and DNS monitoring. This helps avoid tool sprawl and gives you a single place to track everything that matters.

One such tool is Site24x7. It is a comprehensive website monitoring tool that lets you track domain expiry and all key DNS settings and metrics from a central dashboard. You can set up alerts for any unusual changes, track global propagation, and ensure your domain is secure and performing as expected.

Common domain issues and how to troubleshoot

Even with proper setup, domains can run into a variety of problems over time. This section discusses the most common ones.

DNS configuration issues

Let’s start with some common DNS misconfigurations and advice on how to fix them.

Incorrect A or AAAA Records

Your domain isn’t pointing to the correct server IP address.

Symptoms

• Website fails to load or shows a "Server not found" error
• Ping to the domain resolves to the wrong IP address

Troubleshooting

• Log in to your DNS provider and verify the A (IPv4) and AAAA (IPv6) records match your current hosting server’s IP address.
• Use tools like dig, nslookup, or online DNS lookup services to confirm what IP your domain resolves to.
• If you're behind a CDN (like Cloudflare), check that the origin IP is correct and not being overridden.
• Confirm that the record is not set with an unusually short TTL that could be affecting propagation.
• After making changes, clear local DNS cache or test using a public resolver like Google (8.8.8.8) or Cloudflare (1.1.1.1).

Misconfigured MX Records

Email services stop working due to incorrect or missing MX entries.

Symptoms

• Inbound emails are bouncing back or not arriving
• External senders get "mail server not found" or "relay access denied" errors

Troubleshooting

• Check that your MX records point to the correct mail server domain provided by your email hosting provider.
• Make sure there is no trailing dot error (e.g., mail.mysite.com. versus mail.mysite.com).
• Verify that MX priority values are correctly set and not in conflict.
• Confirm that the mail server domain used in the MX record has a valid A or CNAME record.
• Test email flow using command-line tools like dig mx yourdomain.com or tools like MXToolbox.

Missing or Invalid CNAME Records

Your subdomains aren't resolving correctly due to broken aliasing.

Symptoms

• CDN integration or third-party services (like app.example.com) don’t load
• Users get DNS resolution errors when visiting specific subdomains

Troubleshooting

• Review all CNAME records in your DNS panel to ensure they’re pointing to the correct target hostnames.
• Avoid creating CNAME records at the root domain level (RFCs discourage this and many providers block it).
• Confirm that the target of each CNAME resolves to a valid A or AAAA record.
• Be aware of propagation delays when updating CNAME records.
• If using a platform like Heroku or Shopify, check that your domain is properly linked within their dashboard.

Security issues

Next, here are some common security issues to look out for:

WHOIS Record Tampering

Unauthorized changes in WHOIS data can be a sign of domain hijacking or registrar compromise.

Symptoms

• WHOIS lookup shows unfamiliar contact or registrar details
• You receive registrar change or contact update notifications you didn’t initiate

Troubleshooting

• Regularly check your domain’s WHOIS data and verify that the registrant, admin, and tech contacts are accurate.
• If changes are found, contact your domain registrar immediately to confirm if they were authorized.
• Enable registrar lock to prevent unauthorized domain transfers.
• Use WHOIS privacy protection if supported, but still verify the underlying real records in your dashboard.
• Set up monitoring alerts for any changes to WHOIS records.

Missing or Invalid DNSSEC Configuration

Without DNSSEC, DNS records can be spoofed, allowing attackers to redirect traffic.

Symptoms

• DNSSEC validation fails in testing tools
• Users report being redirected to unexpected or malicious sites

Troubleshooting

• Enable DNSSEC in your domain registrar or DNS provider’s dashboard.
• Make sure the DNS zone is properly signed and that DS records are uploaded at the parent zone.
• Test using tools like Verisign DNSSEC Debugger or DNSViz to confirm correct setup.
• Watch for expired or incorrectly rotated DNSSEC keys and renew them as needed.
• If you're unsure of changes, disable DNSSEC temporarily to avoid resolution failures, then reconfigure it properly.

Registration issues

A domain’s registration details are often set and forgotten, which can lead to problems down the line. This section covers some of the most common registration-related problems and how to fix them.

Domain Expired or Nearing Expiration

Expired domains can lead to website and email downtime, and in some cases, loss of ownership.

Symptoms

• Website and email services suddenly stop working
• You receive expiry notices or find the domain listed as available

Troubleshooting

• Regularly check the domain's expiration date through WHOIS, your registrar’s dashboard, or your monitoring tool’s dashboard.
• Set up auto-renewal and ensure your payment information is up to date.
• Set up your monitoring tool to send alerts when a domain is nearing its expiration.
• If the domain has expired, act fast to recover it through your registrar’s grace or redemption period.
• To reduce the chances of missed renewals, try to avoid using multiple registrars for different domains.

Domain Not Properly Renewed After Payment

Sometimes a payment is made, but the domain doesn’t renew due to a registrar-side issue or account misconfiguration.

Symptoms

• You receive a renewal confirmation, but the domain remains in an “expired” or “pending” status
• Services linked to the domain stop working despite recent renewal

Troubleshooting

• After renewing, always confirm that the domain's expiration date has been extended in your account.
• Contact your registrar support if the new expiration date doesn’t reflect the payment.
• Check for failed transactions, especially if multiple payment methods were used.
• Avoid last-minute renewals to give yourself time to catch these kinds of issues.
• Use a centralized domain management tool if you’re managing several domains across different registrars.

Email delivery issues

This section covers common domain-related email delivery issues.

SPF Record Not Set Up

SPF helps email servers verify that your messages are being sent from authorized sources.

Symptoms

• Your emails land in recipients’ spam folders
• You receive delivery failure notices with SPF-related errors

Troubleshooting

• Create a TXT record in DNS with the correct SPF value for your email providers.
• Include all IP addresses and sending services (such as Mailchimp, Google Workspace, etc.).
• Avoid using “+all” or overly broad rules that can weaken your policy.
• Use SPF testing tools to validate your record and confirm it passes checks.
• Review the record regularly when adding or removing sending services.

DKIM Not Enabled

Without DKIM, your emails aren’t cryptographically signed, which makes it easier for others to spoof your domain.

Symptoms

• Increased spoofing attempts using your domain name
• Recipients’ mail servers flag your emails as unauthenticated

Troubleshooting

• Enable DKIM in your email service provider’s settings.
• Publish the provided public key as a TXT record in your DNS under the specified selector.
• Test DKIM signing by sending emails to tools like Mail-Tester or DKIMCore.
• Rotate DKIM keys periodically for better security, especially if compromised.
• Ensure that there’s no mismatch between the selector and what’s published in DNS.

Domain monitoring best practices

Finally, here are some best practices to follow to keep your domain stable and secure:

• Set up auto-renewal for all domains and keep your payment methods up to date.
• Use a registrar that supports two-factor authentication and registrar lock.
• Keep a backup of your DNS zone file in case you need to recover from accidental changes.
• Document your domain setup and renewal process so others on your team can step in if needed.
• Schedule regular audits of your DNS setup, especially after migrations or provider changes.
• Tag or label domains based on priority or business impact to focus alerts and attention.
• Include domain monitoring in your incident response plans and escalation workflows.
• Store access credentials to your registrar and DNS provider securely using a password manager.
• Subscribe to status updates from your registrar or DNS provider in case of outages.
• Include test domains in your monitoring setup to safely experiment with changes without impacting production.
• Review monitoring logs weekly to catch patterns or silent failures.

Conclusion

A formal domain monitoring policy can protect you from unexpected expirations, DNS misconfigurations, and service disruptions that may otherwise go unnoticed until it's too late. We hope that the insights shared in this guide will help you set up a solid monitoring process for your domains.

If you're looking for a simple and effective way to stay on top of your domain health, check out Site24x7. You can sign up for a 30-day free trial to see how it fits your needs.