Network redundancy

Do you have a zombie preparedness plan for your online infrastructure? Well, you should. Even if the zombie apocalypse doesn't come, these strategies are essential for all kinds of disaster preparedness. We are going to be using Constellix DNS to show you how you can create very basic rules to keep your domains online even when the dead rise...

Let's say you have an online business that sells zombie survival equipment and weapons at zombiesurvivalgear.com. You're a mom and pop shop and only need a single web server to host your site because all your users are local.Your website is the clueless blonde that never makes it to the end of a horror movie.... that's because your website is sitting on top of a single point of failure that could mean life and death, not just for you but the whole community dependant on your survival gear.

But you're a savvy prepper and know that the key to withstanding a zombie attack is redundancy.

Failover

Okay, you get another web server, but now you need a way to move traffic from the primary web server to the backup one if something goes wrong. This is called DNS Failover. Quick refresher! DNS (the Domain Name System) maps domain names to human-readable IP addresses and is the glue that holds our modern Internet together. Thanks to the DNS, we don't have to remember long strings of numbers every time we want to browse the web. This "map" is stored in DNS records, which are hosted on authoritative name servers. Your authoritative name server will usually be your DNS hosting provider or domain registrar.

We are going to create a DNS record that maps our domain zombiesurvivalgear.com to our primary web server at 127.11.11.11. That means, whenever someone types zombiesurvivalgear.com into their browser, the authoritative name server will respond with the IP address of our web server.[caption id="attachment_951" align="aligncenter" width="401"]

How to create a basic A record in Constellix[/caption]Now we'll enable Failover, which allows us to specify a backup IP address that our domain will point to in the event our primary IP address is unavailable.[caption id="attachment_949" align="aligncenter" width="748"]

How to setup Failover in Constellix

Failover is integrated with a system of network monitoring nodes that regularly check to see if record endpoints are responding. Once we detect that 127.11.11.11 is "DOWN", the record will automatically change to point to 127.22.22.22.You can learn more about how to setup failover on our knowledge base.And voila! Now your website is safe from the zombie invasion (for now)... stay tuned for our next apocalypse scenario where we show you how to overcome a data center outage (caused by zombies of course) using DNS rules...