The Vultr Load Balancer is a fully-managed solution to distribute traffic to multiple application servers. With a Vultr Load Balancer, you can enable horizontal scaling and increase the reliability of your applications in seconds by setting a few parameters through the customer portal. You don't need to worry about the underlying load balancer server operating system, configuration files, or system management tasks. We handle all the details so you can focus on your application.
This guide is an overview of Load Balancer concepts. If you need more information about a specific feature, the Vultr Load Balancer Feature Reference has detailed configuration information.
Assume you have an e-commerce store with a single web server.
As your store becomes more popular, you need to scale up your site to manage the traffic. You could use a bigger web server, but a better solution might be to use multiple servers and load balancer tools. If you add two more servers and a Vultr Load Balancer, your network looks like this.
Using a load balancer has several advantages.
You can scale your application up and deploy more web servers as the traffic grows.
Just as important, you can scale your application down by removing web servers if the traffic drops.
The Load Balancer detects failed web servers and stops routing traffic to them, improving your application's availability.
Vultr Load Balancers support custom health checks, multiple load balancing algorithms, sticky sessions, proxy protocol, SSL certificates, firewalls, private networks, and more. Vultr Load Balancers work with all our server products, including Bare Metal.
Load balancers are effective for applications that can scale with multiple parallel instances. They distribute the load, but they don't address file synchronization or database consistency between your application instances.
The Vultr Load Balancer has its own integrated firewall. You can learn more in our article How to Use the Vultr Load Balancer Firewall.
The Vultr Firewall can use a Load Balancer as an IP source. We explain more in How to Use the Vultr Firewall with a Vultr Load Balancer.
Explore an advanced scenario with private networking and multiple firewalls in How to Configure a Vultr Load Balancer with Private Networking, where you'll create an advanced configuration like this.
How many connections are allowed?
Load balancers support up to 10,000 simultaneous connections per load balancer.
Can I use a load balancer for servers in multiple regions?
No. A load balancer can only direct traffic for server instances located in the same datacenter location as the load balancer server itself.
Can I use my load balancer in one region with instances in a different region?
Unfortunately not. Load Balancers and attached instances must be in the same region.
My servers are working; why is my health check failing?
If using HTTP or HTTPS protocol, make sure the port and URL path are both correct. The health check looks for HTTP 200 OK success status response code. Any other code is considered unhealthy.
If using TCP protocol, make sure to test an open port on the attached node.
How is bandwidth charged?
Vultr Load Balancers are bandwidth neutral. We only charge on bandwidth on the instances attached to the load balancer.
How do I attach instances to my Vultr Load Balancer?
You can assign and remove instances to your Load Balancer in the Vultr customer portal.
How do I manage my Load Balancer?
You do not have to worry about managing Vultr Load Balancer software. They are fully managed.
What protocols do you support?
Vultr Load Balancers support TCP, HTTP, and HTTPS.
For comprehensive documentation about the Load Balancer features, see the Load Balancer Feature Reference.
Learn how to configure wildcard SSL on your load balancer in our guide Use a Wildcard Let's Encrypt Certificate with Vultr Load Balancer.
See our Load Balancer Feature Reference to learn about limits to the number of forwarding rules.