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DNS Monitor Reference

Overview

Section titled “Overview”

A DNS Monitor is a component designed to verify the availability and correctness of DNS records. It performs periodic lookups for specified DNS record types against a target domain or subdomain from various geographical locations.

Use cases:

  • Validating domain name resolution
  • Monitoring changes to critical DNS records (e.g., A, CNAME, MX)
  • Ensuring proper load balancing via DNS (when combined with multi-region checks)
  • Detecting unauthorized DNS alterations

Configuration

Section titled “Configuration”

URI

Section titled “URI”

Type: String (required) Format: Domain name or subdomain

The fully qualified domain name or subdomain to be monitored.

Examples:

  • openstat.us
  • api.example.com
  • mail.example.org

Record Types

Section titled “Record Types”

The monitor supports fetching and validating the following DNS record types:

  • A (Address Record): Maps a domain name to an IPv4 address.
  • AAAA (IPv6 Address Record): Maps a domain name to an IPv6 address.
  • CNAME (Canonical Name Record): Maps an alias domain name to another canonical domain name.
  • MX (Mail Exchange Record): Specifies the mail servers responsible for accepting email messages on behalf of a domain name.
  • NS (Name Server Record): Delegates a domain or subdomain to a set of authoritative name servers.
  • TXT (Text Record): Carries arbitrary human-readable text and is also used for various purposes like SPF, DKIM, DMARC, and site verification.

Regions

Section titled “Regions”

The geographical locations from which the DNS monitoring checks are performed. This allows for verification of DNS propagation and performance across different networks.

Africa

  • Johannesburg, South Africa 🇿🇦 (free)

Asia

  • Hong Kong, Hong Kong 🇭🇰 (free)
  • Mumbai, India 🇮🇳
  • Singapore, Singapore 🇸🇬
  • Tokyo, Japan 🇯🇵

Europe

  • Amsterdam, Netherlands 🇳🇱 (free)
  • Bucharest, Romania 🇷🇴
  • Frankfurt, Germany 🇩🇪
  • London, United Kingdom 🇬🇧
  • Madrid, Spain 🇪🇸
  • Paris, France 🇫🇷
  • Stockholm, Sweden 🇸🇪
  • Warsaw, Poland 🇵🇱

North America

  • Ashburn, Virginia, USA 🇺🇸 (free)
  • Atlanta, Georgia, USA 🇺🇸
  • Boston, Massachusetts, USA 🇺🇸
  • Chicago, Illinois, USA 🇺🇸
  • Dallas, Texas, USA 🇺🇸
  • Denver, Colorado, USA 🇺🇸
  • Guadalajara, Mexico 🇲🇽
  • Los Angeles, California, USA 🇺🇸
  • Miami, Florida, USA 🇺🇸
  • Montreal, Canada 🇨🇦
  • Phoenix, Arizona, USA 🇺🇸
  • Queretaro, Mexico 🇲🇽
  • Seattle, Washington, USA 🇺🇸
  • San Jose, California, USA 🇺🇸
  • Toronto, Canada 🇨🇦

South America

  • Bogota, Colombia 🇨🇴
  • Buenos Aires, Argentina 🇦🇷
  • Rio de Janeiro, Brazil 🇧🇷
  • Sao Paulo, Brazil 🇧🇷 (free)
  • Santiago, Chile 🇨🇱

Oceania

  • Sydney, Australia 🇦🇺 (free)

Frequency

Section titled “Frequency”

The interval at which the DNS checks are performed. Supported frequencies:

  • 30 seconds
  • 1 minute
  • 5 minutes
  • 10 minutes
  • 30 minutes
  • 1 hour

Response Time Thresholds

Section titled “Response Time Thresholds”

Timeout

Section titled “Timeout”

Type: Duration (optional) Default: 45 seconds

The maximum duration to wait for a DNS response. If the lookup exceeds this time, the check is considered failed.

Degraded

Section titled “Degraded”

Type: Duration (optional)

The duration after which a DNS response is considered degraded. This indicates a performance issue without being a complete failure.

Retry

Section titled “Retry”

Type: Integer (optional) Default: 3

The number of times the monitor will retry a failed DNS lookup before reporting a definitive failure. For example: 3

Section titled “Related resources”