Apache Load Balancer [UPDATED]
When a server gets more traffic than it can handle, delays happen. If it's a web server, then the websites it hosts are slow to respond to user interactions. Services provided are inconsistent, and users could lose data or experience inconvenient interruptions. To prevent this, you can run a load balancer, which distributes traffic loads across several servers running duplicate services to prevent bottlenecks.
apache load balancer
By default, HAProxy uses port number 80. Incoming traffic communicates first with HAProxy, which serves as a reverse proxy and forwards requests to an available endpoint, as defined by the load balancing algorithm you've chosen.
In this example, the frontend sample_httpd listens on port number 80, directing traffic to the default backend sample_httpd with mode tcp. In the backend section, the load balancing algorithm is set to roundrobin. There are several algorithms to choose from, including roundrobin, static-rr, leastconn, first, random, and many more. HAProxy documentation covers these algorithms, so for real-world uses, check to see what works best for your setup.
Managing traffic on your servers is an important skill, and HAProxy is the ideal tool for the job. Load balancing increases reliability and performance while lowering user frustration. HAProxy is a simple, scalable, and effective way of load balancing among busy web servers.
Layer 4 NAT Traditional NAT mode gives easy to implement fast and transparent load balancing but usually requires a two-arm configuration (two subnets).HTTPS443All load balancing methods can be easily configured for SSL Pass-through. This has the advantage of being fast, secure and easy to maintain. Identical SSL certificates will need to exist on each of your backend servers for pass-through security.
SSL Termination or off-loading must be used when advanced Layer 7 functionality such as cookies or URL switching is required. You can also implement SNI if you have multiple domain certificates one public IP address. Optional re-encryption is also available between the load balancer and Apache.HTTP/2N/ALayer 7, support is imminent, this is due/expected in the 8.3.4 timeframe.Proxy ProtocolN/AApache support from v.2.4.31Load Balancing Apache Web Servers with OWASP Top 10 WAF in AzureRead blogguidesApache Web Servers with OWASP Top 10 WAF in Azure Deployment Guide