How to Set Up a PowerDNS Cluster with Poweradmin

Setting up a DNS server cluster can seem daunting, but with PowerDNS and Poweradmin, the process becomes much more manageable. In this guide, we’ll walk you through installing PowerDNS and Poweradmin, configuring them, and setting up clustering between two servers to ensure high availability and redundancy.

What You’ll Need

Two Servers running Ubuntu or a similar Debian-based distribution.
Root or sudo access on both servers.
Basic knowledge of DNS and server administration.

Step-by-Step Guide

1. Install PowerDNS and Poweradmin

On Both Servers

First, update your package list and install the required software.

Update Your Package List:

sudo apt update

Install PowerDNS and MySQL:

sudo apt install pdns-server pdns-backend-mysql mysql-server

Install Poweradmin:

sudo apt install poweradmin

This will install PowerDNS (the DNS server software), MySQL (which PowerDNS will use to store its data), and Poweradmin (a web-based management tool).

2. Configure MySQL for PowerDNS

MySQL will serve as the backend for PowerDNS. You’ll need to create a database and a user for PowerDNS to use.

Access MySQL:

sudo mysql -u root -p

Create the PowerDNS Database and User:

CREATE DATABASE powerdns;
GRANT ALL PRIVILEGES ON powerdns.* TO 'powerdns'@'localhost' IDENTIFIED BY 'your_password';
FLUSH PRIVILEGES;
EXIT;

Initialize the PowerDNS Schema:

sudo mysql -u root -p powerdns < /usr/share/doc/pdns-backend-mysql/schema.sql

This step sets up the necessary tables and structure in your PowerDNS database.

3. Configure PowerDNS

Next, you’ll configure PowerDNS to use MySQL.

Edit the PowerDNS Configuration File:

Open the configuration file:

sudo nano /etc/powerdns/pdns.conf

Add or update the following lines:

launch=gmysql
gmysql-host=127.0.0.1
gmysql-user=powerdns
gmysql-password=your_password
gmysql-dbname=powerdns

Restart PowerDNS:

sudo systemctl restart pdns

This tells PowerDNS to use MySQL as its backend for storing DNS records.

4. Set Up and Configure Poweradmin

Poweradmin provides a web interface for managing DNS records.

Edit the Poweradmin Configuration File:

Open the configuration file:

sudo nano /etc/poweradmin/config.inc.php

Update it with your MySQL credentials:

$conf['db']['host'] = 'localhost';
$conf['db']['user'] = 'powerdns';
$conf['db']['password'] = 'your_password';
$conf['db']['database'] = 'powerdns';

Complete the Poweradmin Setup:

Navigate to Poweradmin in your web browser:

http://your_server_ip/poweradmin/

Follow the on-screen instructions to complete the setup. You’ll be able to manage your DNS records through this interface.

5. Set Up MySQL Replication

To ensure high availability, you’ll set up MySQL replication between the two servers. This way, changes in one server’s database will be mirrored on the other.

Configure the Master Server:

Edit MySQL Configuration:

Open the MySQL configuration file:
Terminal window
```
sudo nano /etc/mysql/my.cnf
```
Add the following lines under the [mysqld] section:
```
server-id = 1
log_bin = /var/log/mysql/mysql-bin.log
```
Restart MySQL:
Terminal window
```
sudo systemctl restart mysql
```

Create a Replication User:

CREATE USER 'replica'@'%' IDENTIFIED BY 'replica_password';
GRANT REPLICATION SLAVE ON *.* TO 'replica'@'%';
FLUSH PRIVILEGES;

Configure the Slave Server:

Edit MySQL Configuration:

Open the MySQL configuration file:
Terminal window
```
sudo nano /etc/mysql/my.cnf
```
Add the following line:
```
server-id = 2
```
Restart MySQL:
Terminal window
```
sudo systemctl restart mysql
```

Set Up Replication on the Slave Server:

CHANGE MASTER TO
  MASTER_HOST='master_server_ip',
  MASTER_USER='replica',
  MASTER_PASSWORD='replica_password',
  MASTER_LOG_FILE='mysql-bin.000001',
  MASTER_LOG_POS= 4;
START SLAVE;

Check Replication Status:

SHOW SLAVE STATUS\G

Ensure the replication process is running smoothly by checking the status output.

6. Test Your DNS Setup

Finally, test to ensure everything is working correctly.

Add DNS Records Using Poweradmin:

Log into Poweradmin and create DNS records to verify that your setup is functioning as expected.

Verify DNS Resolution:

Use tools like dig or nslookup to test DNS queries:

dig @your_server_ip example.com

This will help you confirm that DNS queries are correctly resolved by your servers.

Conclusion

Congratulations! You’ve successfully set up a PowerDNS cluster with Poweradmin. This setup provides redundancy and ensures your DNS services remain available even if one server fails. Remember to secure your servers and regularly back up your data. If you encounter any issues or need further assistance, feel free to ask!