Cloudflare DNS Updater

A utility for updating A records on Cloudflare DNS to point at your current IP, which is ideal if you self-host Internet-facing services but do not have a static IP address. Once configured with a list of domains, this tool will:

• Check your IP address every 2 minutes (configurable).
• Add A records for any domains on your list that aren't configured on Cloudflare.
  • www. prefixes are handled automatically if you want them to be.
• Update existing A records when your IP address changes.
• Optionally remove any A records for domains you haven't configured.

🚀 Jump to quick-start example.

🐳 See releases on ghcr.io.

This work is heavily inspired by timothymiller/cloudflare-ddns and for the most part is just a slightly simplified and more opinionated version.

Configuration

Configuration is split into two parts: a settings file with your list of domains (required) and environment variables for extra options (optional).

Settings File (Domain List)

The main configuration - the list of domains - is stored as a JSON file containing a list of zones to manage. Each zone can have the following properties:

• zoneId - your Cloudflare zone ID
• token - a service token with permission to update DNS records
• ttlSeconds - the TTL value to set when creating new domains (optional, default 120)
• autoWww - whether or not to automatically create and update www-prefixed versions of the domains listed (optional, default false)
• autoDelete - whether or not to automatically remove DNS records for domains you have not specified (optional, default false)
• autoDeleteAllowList - list of regexes for domains that eligible for auto-removal (optional, default empty = all domains are eligible)
• autoDeleteBlockList - list of regexes for domains that ineligible for auto-removal (optional, default empty = all domains are eligible)
• domains - the domains you wish to manage; each should include the TLD and have no leading .

For example:

[
  {
    "zoneId": "xzy-zone1",
    "token": "abracadabra",
    "ttlSeconds": 120,
    "autoWww": true,
    "autoDelete": true,
    "autoDeleteBlockList": ["legacy.example.com"],
    "domains": [
      "example.com",
      "sub1.example.com",
      "sub2.example.com",
      "sub3.example.com"
    ]
  },
  {
    "zoneId": "xzy-zone2",
    "token": "abracadabra",
    "ttlSeconds": 120,
    "autoWww": true,
    "autoDelete": true,
    "autoDeleteAllowList": ["sub.*.example.net"],
    "domains": [
      "example.net",
      "sub1.example.net",
      "sub2.example.net",
      "sub3.example.net"
    ]
  }
]

See types.ts for the full details.

Environment Variables

Variable	Required?	Description	Default
SETTINGS_FILE	no	Path to where your JSON settings file is.	/settings.json
CHECK_INTERVAL_SECONDS	no	How often to re-check your IP address and update records.	120

Quick-Start Docker-Compose Example

version: "3.8"

services:
  cloudflare-dns-updater:
    image: ghcr.io/markormesher/cloudflare-dns-updater:VERSION
    restart: unless-stopped
    volumes:
      - ./settings.json:/settings.json:ro