Run Reliable DNS Servers on VPS with Bind and PowerDNS

Have you ever experienced the frustration of your website going down and thought about how annoying that moment was, and immediately questioned the timing behind it? I certainly have. That’s why high-availability DNS servers on VPS are incredibly useful, and I’d like to share how I set up mine with Bind and PowerDNS and how it may assist keeping your website online forever.

Why High-Availability DNS is Useful​

Consider this: Your site is great, but the only DNS server has gone down. Without DNS, there is no site. High-availability (HA) DNS to the rescue! HA DNS means that you have two or more servers ready to respond to DNS requests on your site.

When one server fails, your visitors still have access to your site via the other server. Since I’ve had HA DNS set up, I’ve felt a lot less anxiety about my site going down.

• Reliable: Your site is working all the time.

• Backup: When one server goes down, another server takes over.

• Faster: Users get a response faster when website server and DNS server are in different geographic areas.

Dilemma of Bind or PowerDNS​

So which DNS software is best for your use? I’ve used both.

Bind

• Old and trusted: This has served people for years.

• Lots of features: Covers even the advanced setups.

• My experience: Hard to get it working, but stable once it's set up.

PowerDNS

• Modern: You can hook into databases or an API.

• Flexible: Easy to manage and automate.

• My experience: Easier to scale and keep an eye on via web dashboard.

I use Bind for the primary websites, while PowerDNS is for services that changed often. And they work great together.

Set Up HA on VPS​

Here's a simple way I'm able to do this:

1. VPS: Two VPS servers in different locations

2. Master-slave setup: Master updates and slave copies everything.

3. Cutover tool: Something like Keepalived will make the switch if a server fails.

4. Monitoring: I have simple scripts that inform if there are no problems.

You don't need a huge setup. Two VPS servers and a little scripting is all you need.

Final Thoughts​

HA DNS might sound like a bad deal. But actually isn't that hard. Either Bind or PowerDNS have given you good tools and you can simply pick a degree of automation. Most of the big websites have stayed online for a long time due to setups like this.