{"id":4755,"date":"2022-08-12T15:21:06","date_gmt":"2022-08-12T13:21:06","guid":{"rendered":"https:\/\/blog.besharp.it\/?p=4755"},"modified":"2022-08-19T10:57:49","modified_gmt":"2022-08-19T08:57:49","slug":"aws-elastic-load-balancing-tips-and-tricks-from-basic-to-pro","status":"publish","type":"post","link":"https:\/\/blog.besharp.it\/aws-elastic-load-balancing-tips-and-tricks-from-basic-to-pro\/","title":{"rendered":"AWS Elastic Load Balancing tips and tricks: from basic to pro"},"content":{"rendered":"\n

An old Italian commercial claimed: “Two is better than one.”<\/p>\n\n\n\n

When it comes to application availability<\/strong>, having multiple instances available makes a business more resilient: this can help you achieve fault tolerance<\/strong> for applications and infrastructures. You know: “Everything can fail, all the time”.<\/p>\n\n\n\n

Load balancing<\/strong> is the fundamental building block that can make us achieve better uptime and application availability: redistributing traffic on different instances in auto scaling and checking their healthiness isn’t always as easy as it seems.<\/p>\n\n\n\n

In my past career as a system administrator, I always struggled to find a resilient, redundant, and elastic solution. After a lot of work and automation, I could have a decent night of sleep!<\/p>\n\n\n\n

Using managed services, as always, can help us reduce the amount of work required to achieve our goals.<\/p>\n\n\n\n

When it comes to load-balancing, AWS gives us a lot of flexibility: under the “Elastic Load Balancing (ELB)” umbrella, many options are available.<\/p>\n\n\n\n

This article will explain ELB fundamentals and deep dive into not-so-common use cases.<\/p>\n\n\n\n

Basic Key Concepts<\/h2>\n\n\n\n

Three managed load balancer types are available: Application<\/strong>, Network<\/strong>, and Gateway<\/strong>.<\/p>\n\n\n\n

In this article, we’ll focus on Application Load Balancers <\/strong>and Network Load Balancers<\/strong>, while we will not consider the Classic Load balancer, as it is a mix of application and network load balancers with some missing features (check this page<\/a> for comparison), and Gateway Load Balancers. We will write about them in a dedicated article.<\/p>\n\n\n\n

Every type of ELB can span multiple Availability Zones and relies on three main components: <\/p>\n\n\n\n