How to Add a Domain Pointing to Multiple IP Addresses
When your website constantly gets many visitors, your server might get overloaded. Constant server downtime may prove to be impactful and costly, especially if you run your business online.
In this case, your domain might need multiple IP addresses to maintain its performance and availability. But how do you add a domain pointing to multiple IP addresses?
In this article, we will look at the definition of a multiple-IP domain, the benefits of having multiple IP addresses, and a few methods of pointing them.
How Does a Multiple IP Domain Work?
When you run a website, you usually use a domain name that points to a single IP address. For example, the domain name.com currently points to 184.108.40.206.
However, websites with high traffic require multiple servers, also known as a server farm or server pool, to run smoothly. That is why some domains will point to multiple IP addresses, as you can see from the example below.
Each server within a server farm is networked to each other and the main server. When using this configuration, your website can typically handle heavier traffic and have better uptime.
When running this kind of network, a method called load balancing is needed. Load balancing can help you route network or application traffic across multiple servers in a server farm systematically.
There are six standard load balancing algorithms. Each comes with its own benefits and can be chosen based on your needs:
- Round robin. Arguably the most straightforward load balancing algorithm. Requests are distributed across the group of servers based on a rotating list.
- Least connections. Distributes traffic to the server with the lowest number of users connected. When deciding which server to choose, each server’s computing capacity is also considered.
- Least time. Users will be directed to a server with the fastest response time and fewest active connections.
- Least bandwidth. Route traffic to a server serving the least amount of traffic as measured in megabits per second (Mbps).
- Least packets. Users will be directed to a service that has received the fewest packets in a given time.
- Hashing. Determines a request based on several data from the incoming packet, including destination IP address, port number, URL, or domain name.
How to Point a Domain to Multiple IP Addresses
In this part, we will look at the general way of setting up load balancing for your domain and web application. The specific steps to point your domain to multiple IP addresses might vary depending on your domain name provider.
1. Setting Up Load-Balancers
A load balancer manages your web traffic by directing it to a server with the highest availability. When implementing a load balancing mechanism to your network, setting up the load-balancer is usually the first step
Install a load balancer or reverse proxy software on each of your web servers. Two of the most common load balancer software are Nginx and HAProxy.
2. Set Up DNS Records
Among the many types of DNS records, DNS A record is the most fundamental. A records hold information about the IP address assigned to a given domain. For example, if you look up the DNS records for upintrendz.com, the A record currently points to 220.127.116.11.
After installing load balancers on each of your web servers, add new A records to your domain through the DNS server setting. After that, assign each new A record with the IP address of the load-balancers you previously installed.
3. Set Up Application Servers
Aside from using it for web servers, load balancing methods are also applicable for other web application services such as mail, FTP, and application servers. The only difference is that you might need to set up additional application servers for it, as multiple servers allow your web application to have higher availability.
Note that it would be better to have backup application servers in different locations when setting up additional application servers. This is to avoid the risk of having all your servers unavailable at the same time.
4. Set Up Databases
Pay attention to your databases when setting up load balancing for a web application. Just like application servers, it is also important to have multiple databases placed in different locations.
Depending on your type of database server, it is best to create a duplicated configuration across multiple servers. Additionally, each primary server should be accompanied by one or two slave servers to back it up physically.
The main benefit of a load balancing mechanism is that it will improve your website performance and availability. Methods such as round-robin DNS allow traffic to be evenly distributed to multiple servers, lowering the risk of server overloading.
In this article, we have learned about the definition of a multiple-IP domain and the benefit of having multiple IP addresses. We also discussed ways of pointing your domain to multiple IP addresses, including:
- Setting up load-balancers
- Setting up DNS records
- Setting up application servers
- Setting up databases
Hopefully, this article gives you a general idea of how to point your domain to multiple IP addresses. To find out the detailed steps of setting up load balancing for your domain, make sure to contact your provider or go to their knowledge base.