🏥 DNS Health Check

Validate DNS redundancy, consistency, and reachability for any domain.

Why DNS Health Matters?

A poor DNS configuration can lead to intermittent website downtime and slow performance. Health checks ensures your servers are responding correctly and are in sync.

Critical DNS Health Metrics

  • Redundancy: Having multiple nameservers in different locations/networks. Having multiple nameservers in different locations/networks.
  • Consistency: Ensuring all nameservers return the same records. Ensuring all nameservers return the same records.
  • Lame Delegation: Checking if nameservers are actually authoritative for the domain. Checking if nameservers are actually authoritative for the domain.
  • SOA Records: Validating the Start of Authority parameters. Validating the Start of Authority parameters.

A DNS Health Check tool analyzes Domain Name System configuration to identify issues with nameserver redundancy, record consistency, SOA parameters, and delegation, helping prevent DNS-related outages.

Key Facts

  • DNS resolution adds 20-120ms to every web request
  • 72% of DNS outages are caused by configuration errors
  • The average DNS TTL is 300 seconds
  • There are 13 root DNS server clusters worldwide

Frequently Asked Questions

What is DNS?

DNS translates domain names like example.com into IP addresses. It is the phonebook of the internet.

How many nameservers should I have?

At least 2 on different networks. Many organizations use 3-4 for optimal redundancy.

What is a SOA record?

SOA contains administrative info about a DNS zone: primary nameserver, admin email, serial number, and timing parameters.

What is lame delegation?

When a nameserver is listed as authoritative but cannot answer queries. A serious misconfiguration causing intermittent failures.

How often should I check DNS health?

After any DNS changes, monthly for production domains, and immediately if experiencing accessibility issues.