Load balancing lets you evenly distribute your work, or load, across two or more servers to avoid a massive overload on any one machine. Instead of web page requests being sent directly to a server, they get shuttled over to your network load balancer which, in turn, sends the request to one of your servers. That server then sends a message back to the load balancer indicating if it’s able to handle the request and, if not, the load balancer goes into action sending out the request until it finds a server that can.
Why you want it
Developers have a wide range of reasons to want a load balancer. Evenly distributing your load helps:
- Significantly reduce downtime
- Significantly increase availability
- Keep your network up and running even if a server goes down
Instead of trying to solve an overload issue with a new server, more memory, network cards or other hardware, a load balancer takes care of the issues by taking care of the root cause of the problem.
What you need to get it
Once you decide load balancing is what you want, your next move is to make it happen. Load balancing requires:
· Virtual IP:
Your virtual IP is the address at which your application can be found, typically a combination of the IP address seen by the public and the DNS name.
· List of Servers:
This list contains the servers across which you’ll be balancing the load. The servers as a whole are otherwise known as your “pool,” or available servers that are up for the task of taking on part of the workload.
· List of IP Addresses:
Here’s where you list the IP addresses and port combinations on which your application can be found. They may be entries within your pool and may contain information that goes far beyond just an IP address and name.
·Algorithm:
The final step is creating an algorithm that tells your load balancer how you want it to distribute your incoming requests. You can keep it simple with the commonly used “round robin” which, as the name indicates, tells your load balancer to go around to each server to check for availability, repeating the process until it finds one that can handle it. Algorithms can get much more complex from there, depending on what you need to best suit your network.
Handing Over the Hassle
Opting for a load balancing provider lets you avoid the hassle of setting up an in-house load balancer in the first place. Providers can typically set you up with a balancer with a few clicks of the mouse instead of a few days poring over details. You’ll often be treated to an online control panel to manage the balancer, the flexibility of choosing your own algorithms and protocols and a static IP address to keep things consistent. Some providers may offer short-term contracts and any quality one will give you a full slate of support.
Heavy loads can be hell, both on your mindset and your network, and load balancers can ensure no single heavy load bombs your whole system. That takes care of your network. You can take care of the heavy load mindset by opting for a provider that does the heavy lifting for you.