VoIP Toolbox

DNS Monitoring

Get alerted when your SIP-related DNS changes. Monitor SRV records and the A/AAAA targets they resolve to, so you catch changes that break routing before tickets arrive.

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How it works

  1. 1 Pick a domain to monitor (SIP-friendly: SRV + A/AAAA).
  2. 2 We resolve and compare SRV records and the hostnames they point to.
  3. 3 You get alerts + history when anything changes.

Example alert

A change you actually care about: SRV is stable, but the target IP changes.

DNS change detected
_sip._udp.sip.example.com SRV target
sip-edge-01.example.net
A record 198.51.100.10 → 198.51.100.42
Saved to history with first-seen/last-seen timestamps.

SRV-aware monitoring

Track _sip._udp, _sip._tcp, and _sips._tcp records and detect changes.

Multi-level change detection

Alerts fire if the SRV record changes or if the SRV target hostnames resolve to different A/AAAA answers.

History you can trust

Keep a timeline of DNS states with first-seen/last-seen timestamps for incident reports and postmortems.

About DNS Monitoring

DNS Monitoring allows you to continuously monitor your domain's DNS records and receive instant email notifications when changes are detected. This helps you track DNS stability and ensures your services remain accessible. Especially useful for SIP infrastructure - our monitoring performs comprehensive SRV and A record lookups, detecting changes at the top level (SRV records) or in underlying data (A/AAAA records).

How It Works

  • Comprehensive DNS Lookups: Performs the same detailed DNS lookups as our DNS lookup tool - SRV, A, AAAA, and CNAME records
  • Hostname Resolution: Automatically resolves SRV target hostnames to their A and AAAA records
  • Change Detection: Compares current DNS results with previous checks using hash-based comparison
  • Multi-Level Monitoring: Detects changes in SRV records OR their underlying A/AAAA targets
  • Configurable Check Frequency: Set monitoring intervals from every 15 minutes to once per day
  • Email Alerts: Receive instant email notifications when DNS changes are detected
  • History Tracking: View complete history of DNS changes with first seen/last seen timestamps

Perfect for SIP Services

DNS Monitoring is especially valuable for SIP (Session Initiation Protocol) infrastructure. When you monitor a SIP domain:

  • SRV Record Monitoring: We check for SIP service records (_sip._tcp, _sip._udp, _sips._tcp, etc.)
  • Automatic Hostname Resolution: Each SRV record's target hostname is automatically resolved to A and AAAA records
  • Complete Change Detection: You'll be alerted if SRV records change OR if the underlying A/AAAA records change
  • Same Lookup Logic: Uses the same comprehensive DNS lookup method as our DNS lookup tool for consistency

Example: If you monitor sip.example.com, we'll check for SRV records (like _sip._tcp.sip.example.com), resolve any target hostnames to A/AAAA records, and alert you if any of these records change - whether it's the SRV record itself or the IP addresses it points to.

Monitoring Features

  • Flexible Frequency: Choose from 15 minutes, 30 minutes, 1 hour, 3 hours, 6 hours, 12 hours, or once per day
  • Custom Alert Emails: Use your account email or specify a custom email address for alerts
  • Active/Inactive Toggle: Enable or disable monitoring for any domain without deleting the configuration
  • Complete History: View all DNS states over time - each unique DNS configuration is tracked with first seen and last seen timestamps
  • Detailed View: Click any history entry to see the complete DNS records, just like our DNS lookup tool

Tier Limits

  • Free: Monitor 1 domain
  • Core: Monitor up to 10 domains
  • Professional: Monitor up to 50 domains