iptracker

A DNS A record updater that monitors your public IPv4 address and keeps PowerDNS records in sync. When your IP changes, iptracker updates the configured records and can notify you via Discord or ntfy.

Usage

One-shot mode

Check and update once, then exit:

iptracker \
  --pdns_apikey=your-api-key \
  --pdns_url=http://powerdns:8081 \
  --rrset=myhost.example.com,example.com. \
  --rrset=otherhost.example.com,example.com.

Daemon mode

Run continuously, checking at a regular interval:

iptracker \
  --pdns_apikey=your-api-key \
  --pdns_url=http://powerdns:8081 \
  --rrset=myhost.example.com,example.com. \
  --background \
  --interval=5m

Flags

Flag	Description	Default
--pdns_apikey	PowerDNS API key (required)
--pdns_url	PowerDNS API URL (required)
--rrset / -r	Comma-separated record,zone tuple; repeatable (required)
--background / -b	Run as a continuous daemon	false
--interval / -i	Check interval in daemon mode	5m
--discord / -d	Discord webhook URL
--ntfy / -n	ntfy webhook URL

Record names must be fully qualified (e.g. myhost.example.com. with trailing dot).

Docker Compose

services:
  iptracker:
    build: .
    command: >
      --pdns_apikey=your-api-key
      --pdns_url=http://powerdns:8081
      --rrset=myhost.example.com.,example.com.
      --background
      --interval=5m
      --ntfy=http://ntfy/example
    restart: unless-stopped

Development

Prerequisites

• Go 1.26+
• Docker (for integration tests)

Unit tests

make test

Integration tests

Integration tests require PowerDNS and ntfy running in Docker:

make test-integration

This starts the containers, runs the tests, and leaves the containers running for inspection. Tear down when done:

make clean-integration

To run a specific integration test:

docker compose -f docker-compose.integration.yml up -d --wait
go test -tags=integration -timeout 120s -v -run=TestIntegration_PowerDNS_UpdateRecord ./...
make clean-integration

Test coverage

make coverage

Build

go build -o iptracker .

Docker build

docker build -t iptracker .

Project structure

File	Purpose
main.go	CLI flags, validation, daemon loop, signal handling
ip.go	Public IP detection via ifconfig.me
update.go	Single DNS record update logic
cycle.go	Orchestrates parallel updates and notifications; webhook URL validation
notify.go	Discord and ntfy notification senders
client.go	RecordsClient interface and PowerDNS implementation
rrset.go	RRSet type and pflag.Value implementation
errors.go	IPCheckError, RecordUpdateError, NotificationError
transport.go	HTTP transport that sets curl User-Agent

Error types

All errors implement Unwrap() for use with errors.Is / errors.As:

• IPCheckError — failures reaching or parsing the IP check service
• RecordUpdateError — DNS record fetch/update failures (carries Record and Zone)
• NotificationError — Discord/ntfy delivery failures (carries Service)