There is a technique that could make it work, sort-of: round robin DNS. You can add two DNS records for the same name with two different IP addresses. In theory, clients should get one of two of the IP values and half your traffic should hit each of your servers.
In practice round robin DNS has problems:
- One of your servers will end up getting more traffic than the other. This is due to DNS servers making a choice for all their users and serving just one of the two values to many users.
- If one of your servers goes down, the half of users that would hit it won't be able to get to your site. There is nothing that will route them to the other server that is still up. This makes your site twice as fragile as it was with only one server and makes it hard to do scheduled down time and maintenance.
It is better to get two servers at the same web host and put a load balancer in front of them. A load balancer only works on a local network, but it routes traffic to servers based on whether or not they are actually up. It also allows you to control traffic percentages much better.
With either round robin DNS or a load balancer, you will need two central things to run WordPress:
- Your database which stores posts and users
wp-content directory which stores images and themes
To use two servers, you will need to set both of them up to use a central database and a network file system for wp-content.
Another option is to continue with a single server but put a content delivery network (CDN) in front of it. A CDN is a set of caching proxy servers designed to be close to your users. A CDN will reduce the load on your main server while making your site faster for users. Because there is caching, it is hard to use this technique with highly dynamic websites.