DNS troubleshooting and common issues
Overview
DNS issues are the most common reason why a website won't load or an email isn't delivered. Because DNS relies on thousands of servers across the globe talking to each other, a single typo or a slow "update period" (propagation) can cause a service to go offline.
This guide helps you identify the symptoms and provides the exact steps to get your domain back on track.
1. Symptom: The domain won't load at all
If you type your domain into a browser and see a "Server Not Found" error, the "address book" of the internet is likely broken.
- Check the Nameservers: If you registered your domain with DotSync, verify that your nameservers are set to default.
- External Providers: If you use a third-party (like Cloudflare or GoDaddy) for your DNS, ensure you have an A record pointing to your web host's IP address.
- The "Trace" Test: Advanced users can run
dig +trace yourdomain.comin a terminal to see exactly where the connection is dropping.
2. Symptom: Changes aren't showing (Slow Propagation)
DNS changes do not happen instantly. Every record has a TTL (Time to Live), which tells other computers how long to "remember" the old setting before checking for a new one.
- High TTL: If your TTL was set to 3600 (1 hour), the rest of the world might not see your change for 60 minutes.
- The Fix: If you are planning a move, lower your TTL to 300 (5 minutes) at least 24 hours before you make the actual change.
- Clear Your Cache: Sometimes your own computer is "remembering" the old site. Try opening your site in an Incognito/Private window or use a public tool like DNS Checker to see the global status.
3. Symptom: SSL/Security Certificate Failures
If you see a "Your connection is not private" warning, your SSL certificate is failing to validate.
- Check Validation Records: Some certificates require a special TXT or CNAME record (often starting with
_acme-challenge) to prove you own the domain. Ensure these haven't been deleted. - Point to DotSync: If you are using DotSync's automatic SSL, ensure your A or CNAME record is pointing correctly and that the SSL & CDN toggle is turned ON in your dashboard.
- Wildcard Certificates: If you are trying to secure
*.yourdomain.com, you almost always need to use a DNS TXT record for validation.
4. Symptom: Errors with the "Root" Domain
A common technical mistake is trying to use a CNAME for your main domain (example.com). According to official internet rules, this is not allowed and will break your email.
- The Fix: If a service asks you to "alias" your root domain, use DotSync’s ALIAS record type. This provides the functionality of a CNAME but follows the rules of the internet, keeping your email and website working perfectly.
Technical Toolbox
If you are comfortable with a terminal/command line, use these commands to see what is happening under the hood:
| Command | Purpose |
|---|---|
dig yourdomain.com +short | Quickly see which IP address your domain is pointing to. |
dig yourdomain.com MX | Check if your email records are active. |
dig _acme-challenge.yourdomain.com TXT | Verify your security certificate's "handshake" record. |
When to Contact Support
If you have checked your records and the DNS Checker shows that everything is correct, but your service is still offline, it may be a more complex issue like DNSSEC misconfiguration.
When contacting support, please include:
- The specific domain or subdomain (e.g.,
shop.yourcompany.com). - The record you expect to see (e.g., "It should be pointing to IP 1.2.3.4").
- A screenshot of any error message you see in your browser.