What is host name affinity in Server Farm -> Server Affinity on IIS 8 Web Farm?

Question

The problem is I have 2 IIS Servers working as Web Farm and currently we don't use Client Affinity or Host Name affinity. I just need to know what is the benefits of using Host Name affinity and when we use this type of affinity between Server and Client. I already have information about Client Affinity I just need to get more information about Host Name Affinity and when to use it. Thank you guys for help in advance.

Answer 1

Application Request Routing (ARR) provides client and host name affinity features that enable you to provide stickiness between clients and servers. Host name affinity lets you map a host name to a server so that all requests for the same host name are routed to the same server. Client affinity is used to map a client to an application server behind ARR for the duration of the client session. A load balance algorithm is used for the first request from the client. Subsequent requests from the same client are routed to the application server for the duration of the client session. noteNote

You can use client affinity and host name affinity together. When both are configured, if a host name is affinitized to multiple servers, client affinity is applied within the allocated and host name affinitized application servers.

^From: Technet

Using host name affinity you can control how many servers a host name (eg example.com) is allowed to be served on simultaneously (eg 2) as well as see which server(s) it is currently being routed to (eg server1) in the routing table and release routes to have the next request go back into the load balancing algorithm you have selected (eg server1 or server2).