Application Load Balancer received upgrade last summer as redirect and fixed responses were introduced as new actions. Therefore, action possibilities contains at the moment Forward, Authenticate (HTTPS listener only), Redirect, and Fixed responses. These two latest actions enable some simplifications to the environment.
I find the Redirect very useful and a real word example is HTTP to HTTPS redirect. HTTP requests don’t need to reach the webserver anymore for HTTP -> HTTPS redirect as the magic happens at the load balancer. Apache/NGINX can be configured to listen only one traffic port as all traffic will be routed through that port. For setting HTTP-> HTTPS redirect up at the ALB, it is only required to select HTTP Listener and a new rule; first the Condition (either Path or Host) and then Redirect Action and type 443 in to the console. The result is that all HTTP requests are redirected to HTTPS.
Figure 1. Redirect as a new action.
The trend is to move some of the activities away from webserver to the load balancer and utilizing a fixed response is one. For example, certain HTTP error codes can be handled on the load balancer level. Clearly some benefits, but I see that the Redirect will be somewhat more widely used.
Even though these new features will make life somewhat easier, there is one feature that still remains on my wish list. Support for the Application controlled session cookies.