> ## Documentation Index
> Fetch the complete documentation index at: https://kmerhosting.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Troubleshoot domains and DNS

> Diagnose propagation, nameserver, record, website, email, and certificate issues.

Domain problems often involve several independent layers: registration, nameservers, DNS records, hosting attachment, application configuration, email records, and SSL.

<Frame caption="Record the intended DNS values before changing them.">
  <img src="https://mintcdn.com/kmerhosting-a736a8a9/qmzUGdL1AajWuhXn/images/screenshots/domain-dns-records.png?fit=max&auto=format&n=qmzUGdL1AajWuhXn&q=85&s=f4e829b396ed0609da29d902e59995ac" alt="Record the intended DNS values before changing them." width="1600" height="900" data-path="images/screenshots/domain-dns-records.png" />
</Frame>

## Diagnostic order

1. Confirm the domain is active and not expired.
2. Verify authoritative nameservers.
3. Query the required DNS record.
4. Confirm the target server or service is reachable.
5. Check the hosting domain attachment.
6. Test HTTP and HTTPS.
7. Check MX and TXT records separately for email.

## Propagation

Cached resolvers can show old values after a correct change. Compare multiple resolvers and wait for the previous TTL where necessary.