Cloudflare DNS Updater

Table of Contents

1. Description
2. Features
3. Requirements
4. Installation
5. Configuration
6. Usage
7. Examples
8. Flowcharts
9. Dependencies
10. Troubleshooting
11. Contributing
12. License

Description

Cloudflare DNS Updater is a bash script designed to automate the management of DNS records in Cloudflare. It allows updating A (IPv4) and AAAA (IPv6) records for multiple domains, offering flexible configuration options and various notification methods.

Features

• DNS Record Management:

  • Update A (IPv4) and AAAA (IPv6) records
  • Support for multiple domains
  • Create new DNS records if they don't exist (optional)
  • Delete DNS records when IPv4 or IPv6 is set to false

• Configuration:

  • YAML configuration file for easy setup
  • Command-line options for quick adjustments
  • Support for environment variables for sensitive data

• Performance:

  • Parallel processing of domains
  • Configurable retry mechanism for API requests

• Testing and Debugging:

  • Test mode (dry run) for verification without making changes
  • Extensive logging capabilities
  • Debug mode for detailed output

• Notification Systems:

  • Multiple notification methods (Email, Telegram, Slack, Discord)

• User Interface:

  • Colorized terminal output with progress indication
  • Man page for easy reference

Requirements

Mandatory

• Bash 4.0+
• curl
• jq (JSON parser)

Recommended

• yq (YAML parser)

Optional

• openssl (for email notifications)
• netcat (for email notifications)

Installation

1. Clone the repository:

   git clone https://github.com/yourusername/cloudflare-dns-updater.git

2. Make the script executable:

   chmod +x cloudflare-dns.sh

3. (Optional) Copy the script to a directory in your PATH for system-wide access:

   sudo cp cloudflare-dns.sh /usr/local/bin/cloudflare-dns

4. (Optional) Install the man page:

   sudo mkdir -p /usr/local/man/man1
   sudo cp cloudflare-dns.1 /usr/local/man/man1/
   sudo mandb

Configuration

Create a YAML configuration file named cloudflare-dns.yaml in the same directory as the script or specify a custom path using the -c option. Here's an example configuration:

# Cloudflare account settings
cloudflare:
  zone_id: "your_zone_id_here"
  zone_api_token: "your_api_token_here"

# Global settings (applied to all domains unless overridden)
globals:
  ipv4: true
  ipv6: true
  proxied: true
  ttl: auto
  enable_create_record: false

# Domain-specific settings
domains:
  - name: example.com
    ipv4: true
    ipv6: true
    proxied: true
    ttl: 1
  - name: subdomain.example.com
    ipv4: true
    ipv6: false
    proxied: false
    ttl: 3600

# Advanced settings
advanced:
  retry_attempts: 3
  retry_interval: 5
  max_parallel_jobs: 5

# Notification settings
notifications:
  telegram:
    enabled: false
    bot_token: "your_telegram_bot_token"
    chat_id: "your_telegram_chat_id"
  email:
    enabled: true
    smtp_server: "smtp.example.com"
    smtp_port: 587
    use_ssl: true
    username: "[email protected]"
    password: "your_email_password"
    from_address: "[email protected]"
    to_address: "[email protected]"
    subject: "Cloudflare DNS Update Notification"
  slack:
    enabled: false
    webhook_url: "https://hooks.slack.com/services/YOUR/SLACK/WEBHOOK"
  discord:
    enabled: false
    webhook_url: "https://discord.com/api/webhooks/YOUR/DISCORD/WEBHOOK"

# Logging settings
logging:
  file: "cloudflare-dns.log"
  terminal_output: true
  verbosity: "success"
  max_size: 10485760  # 10 MB in bytes
  rotate_count: 5
  compress_days: 7
  clean_days: 30
  log_to_system: false
  sanitize_logs: true

How to obtain Cloudflare API Token and Zone ID

1. API Token:

   • Log in to your Cloudflare account.
   • Go to "My Profile" > "API Tokens".
   • Click "Create Token".
   • Use the "Edit zone DNS" template or create a custom token with the necessary permissions Copy the generated token.

2. Zone ID:

   • Log in to your Cloudflare account.
   • Select the domain you want to manage.
   • The Zone ID is displayed on the right side of the overview page.
   • Copy the Zone ID.

Usage

Basic usage:

cloudflare-dns [COMMAND] [OPTIONS]

Commands

Command	Description
update	Update DNS records for specified domains
test	Run in test mode (dry run) without making changes
help	Show help message and exit

Options

Option	Description	Default Value
-h, --help	Show help message and exit	-
-c, --config FILE	Specify the configuration file	cloudflare-dns.yaml
-q, --quiet	Disable terminal output	false
-v, --verbosity LEVEL	Set log verbosity level	success
-p, --parallel NUM	Set the maximum number of parallel jobs	1
--version	Show version information and exit	-

Update Command Options

Option	Description	Default Value
--zone-id ID	Cloudflare Zone ID	-
--token TOKEN	Cloudflare API Token	-
--domains D1,D2,...	Comma-separated list of domains to update	-
--ipv4 BOOL	Update IPv4 records	true
--ipv6 BOOL	Update IPv6 records	true
--proxied BOOL	Enable Cloudflare proxying	true
--ttl NUM	Set TTL for DNS records	1 (Auto)
--create-record BOOL	Enable creation of missing records	false

Logging Options

Option	Description	Default Value
--log-file FILE	Specify log file	cloudflare-dns.log
--log-max-size BYTES	Maximum log file size before rotation	10485760 (10MB)
--log-rotate-count NUM	Number of rotated log files to keep	5
--log-compress-days NUM	Days after which to compress old logs	7
--log-clean-days NUM	Days after which to delete old logs	30
--log-to-system BOOL	Send logs to the operating system's logging system	false
--disable-log-sanitization	Disable sanitization of sensitive information in logs	false

Verbosity Levels

The --verbosity option accepts the following levels:

• debug_logging: Most detailed logging, including debug information about the logging system itself
• debug: Detailed information, typically of interest only when diagnosing problems
• info: Confirmation that things are working as expected
• warning: An indication that something unexpected happened, or indicative of some problem in the near future
• error: Due to a more serious problem, the software has not been able to perform some function
• success: Information about successful operations (default)

Environment Variables

Variable	Description
CF_API_TOKEN	Cloudflare API Token (overrides config file and --token)
CF_ZONE_ID	Cloudflare Zone ID (overrides config file and --zone-id)

Examples

1. Update DNS records using the default configuration file:

   cloudflare-dns update

2. Update DNS records using a custom configuration file:

   cloudflare-dns update -c my_config.yaml

3. Run in test mode (dry run) without making changes:

   cloudflare-dns test

4. Update specific domains:

   cloudflare-dns update --domains example.com,subdomain.example.com

5. Use environment variables for sensitive data:

   export CF_API_TOKEN="your_api_token_here"
   export CF_ZONE_ID="your_zone_id_here"
   cloudflare-dns update

   Or:

   CF_API_TOKEN=your_token CF_ZONE_ID=your_zone_id cloudflare-dns update

6. Update DNS records with custom options:

   cloudflare-dns update --ipv4 false --ipv6 true --proxied false --ttl 3600

7. Run with custom logging options:

   cloudflare-dns update --log-file /var/log/cf-dns-update.log --log-max-size 20971520 --log-rotate-count 10 --verbosity debug

8. Enable system logging and disable log sanitization:

   cloudflare-dns update --log-to-system true --disable-log-sanitization

Step-by-step Example: Configuring and Updating Multiple Domains

1. Create a configuration file cloudflare-dns.yaml:

   cloudflare:
     zone_id: "44d43a33307a232a60a5af4fc1504613"
     zone_api_token: "rY7s0ciXH9ARs3FkxChCdBIti_X15oT_bSUN7xQP"
   
   globals:
     ipv4: true
     ipv6: true
     proxied: true
     ttl: auto
   
   domains:
     - name: example.com
     - name: blog.example.com
       ipv6: false
     - name: api.example.com
       proxied: false
       ttl: 3600
   
   advanced:
     retry_attempts: 3
     retry_interval: 5
     max_parallel_jobs: 2
   
   notifications:
     email:
       enabled: true
       smtp_server: "smtp.gmail.com"
       smtp_port: 587
       use_ssl: true
       username: "[email protected]"
       password: "your_gmail_app_password"
       from_address: "[email protected]"
       to_address: "[email protected]"
   
   logging:
     file: "cloudflare-dns.log"
     terminal_output: true
     verbosity: "info"

2. Run the script in test mode:

   cloudflare-dns test -c cloudflare-dns.yaml

   This will show what changes would be made without actually applying them.

3. If satisfied with the proposed changes, run the script to update the records:

   cloudflare-dns update -c cloudflare-dns.yaml

4. Review the terminal output and log file to confirm the changes were applied correctly.

Flowcharts

This section provides visual representations of the script's workflow and decision-making processes. These flowcharts aim to help users understand the inner workings of the Cloudflare DNS Updater script.

Main Script Flowchart

The following diagram illustrates the main flow of the script, from startup to completion:

graph TD
    A[Start Script] --> B[Parse Command Line Arguments]
    B --> C[Load Configuration]
    C --> D[Validate Configuration]
    D --> E[Initialize Logging]
    E --> F{Command?}
    F -->|Update| G[Get Current IPs]
    G --> H[Process Domains]
    H --> I[Display Summary]
    I --> J[Send Notifications]
    F -->|Test| K[Run Test Mode]
    F -->|Help| L[Display Help]
    J & K & L --> M[End Script]

    subgraph Process Domains
        H --> N{Parallel Processing?}
        N -->|Yes| O[Process Domains in Parallel]
        N -->|No| P[Process Domains Sequentially]
    end

Loading

This flowchart shows the overall structure of the script, including configuration loading, command processing, and the main update process.

Domain Processing Flowchart

The following diagram details how each domain is processed:

graph TD
    A[Start Domain Processing] --> B{IPv4 Enabled?}
    B -->|Yes| C[Get Local IPv4]
    B -->|No| D{IPv6 Enabled?}
    C --> E[Process A Record]
    E --> D
    D -->|Yes| F[Get Local IPv6]
    D -->|No| G[End Domain Processing]
    F --> H[Process AAAA Record]
    H --> G

    subgraph Process DNS Record
        E & H --> I{Record Exists?}
        I -->|Yes| J{Needs Update?}
        I -->|No| K{Create Enabled?}
        J -->|Yes| L[Update Record]
        J -->|No| M[No Changes]
        K -->|Yes| N[Create New Record]
        K -->|No| O[Log Error]
        L & M & N & O --> P[Log Changes]
    end

    B -->|No| Q[Delete A Record]
    D -->|No| R[Delete AAAA Record]
    Q & R --> P

Loading

This flowchart illustrates how the script handles both IPv4 (A records) and IPv6 (AAAA records) for each domain, including the decision process for updating, creating, or deleting records.

Update DNS Record Flowchart

The following diagram shows the detailed process of updating a single DNS record:

graph TD
    A[Start Update DNS Record] --> B{Record Exists?}
    B -->|Yes| C[Get Current Record Info]
    B -->|No| D{Create Enabled?}
    C --> E{Changes Needed?}
    E -->|Yes| F[Prepare Update Payload]
    E -->|No| G[No Changes Needed]
    F --> H[Send API Request]
    H --> I{API Success?}
    I -->|Yes| J[Log Success]
    I -->|No| K[Log Error]
    D -->|Yes| L[Create New Record]
    D -->|No| M[Log Error]
    G & J & K & L & M --> N[End Update DNS Record]

    subgraph Changes Checked
        E --> O{IP Changed?}
        E --> P{Proxied Status Changed?}
        E --> Q{TTL Changed?}
    end

Loading

This flowchart provides a detailed view of how the script determines whether a DNS record needs to be updated and the steps involved in the update process.

These flowcharts are designed to be interconnected, with the Domain Processing Flowchart being a more detailed view of the "Process Domains" step in the Main Script Flowchart, and the Update DNS Record Flowchart expanding on the "Process DNS Record" subgraph in the Domain Processing Flowchart.

Dependencies

Bash 4.0+ (Required)

Generally pre-installed on Linux systems. On macOS, you can update it using Homebrew:

brew install bash

More information about Bash.

curl (Required)

Tool for transferring data with URL syntax. Installation:

• On Ubuntu/Debian: sudo apt-get install curl
• On CentOS/Fedora: sudo yum install curl
• On macOS with Homebrew: brew install curl

More information about curl.

jq (Required)

Command-line JSON processor. Installation:

• On Ubuntu/Debian: sudo apt-get install jq
• On CentOS/Fedora: sudo yum install jq
• On macOS with Homebrew: brew install jq

More information about jq.

yq (Optional. Required for using YAML configuration)

Command-line YAML processor. Installation:

• On Ubuntu/Debian: sudo apt-get install yq
• On CentOS/Fedora: sudo yum install yq
• On macOS with Homebrew: brew install yq

More information about yq.

openssl (Optional. Required for SSL/TLS connections in email notifications)

Cryptography toolkit. Generally pre-installed. If not:

• On Ubuntu/Debian: sudo apt-get install openssl
• On CentOS/Fedora: sudo yum install openssl
• On macOS with Homebrew: brew install openssl

More information about openssl.

netcat (Optional. Required for email notifications)

Networking utility for reading from and writing to network connections. Installation:

• On Ubuntu/Debian: sudo apt-get install netcat
• On CentOS/Fedora: sudo yum install netcat
• On macOS with Homebrew: brew install netcat

More information about netcat.

Troubleshooting

1. Script cannot connect to Cloudflare API
   • Check your internet connection.
   • Ensure your Cloudflare API token is valid and has the correct permissions.
   • Review debug logs for more information.
   • Verify that the Cloudflare API endpoint is not blocked by your firewall.
2. DNS records are not updating
   • Confirm that domains are correctly configured in the YAML file.
   • Verify that you have permissions to modify DNS records in Cloudflare.
   • Run the script in debug mode for more details.
   • Check if the Cloudflare zone (domain) is active and not pending.
3. Notifications are not being sent
   • Review notification settings in the YAML file.
   • Ensure your notification service credentials are correct.
   • Verify that your mail server or webhook service is functioning properly.
   • Check your firewall settings to ensure outgoing connections are allowed.
4. Script is running slowly
   • Reduce the number of domains being processed simultaneously.
   • Check your internet connection speed.
   • Ensure that your system's DNS resolution is working correctly.
5. Error: "jq: command not found" or similar
   • Make sure all dependencies are installed correctly.
   • Verify that the installed tools are in your system's PATH.
   • Try reinstalling the missing dependency.
6. YAML parsing errors
   • Validate your YAML configuration file syntax. Use an online YAML validator or a linter. Examples: YAML Lint, Online YAML Parser.
   • Ensure there are no tabs used for indentation (use spaces instead).
   • Check for any special characters that might need to be escaped.
7. Permission denied errors
   • Ensure the script has execute permissions (chmod +x cloudflare-dns.sh).
   • Check if you have write permissions for the log file directory.
8. API rate limiting issues
   • Increase the retry_interval in the advanced settings.
   • Reduce the max_parallel_jobs to lower the number of simultaneous API calls.

For additional help, review the debug logs or open an issue on the GitHub repository.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request (AKA Merge Request) with your changes or improvements. If you encounter any issues or have suggestions for new features, please open an issue on the GitHub repository.

License

This project is licensed under the GNU General Public License v3.0. For more information, see the LICENSE file.