IIS failover Clusters?

Question

I'm new to servers and stuff(I'm a programmer not a server guy) and I have a question about IIS failover clustering. I have two IIS servers up and running, and they're identical. I want to set up the servers as a failover cluster. I want to set it up so that Server A is the main server and Server B is a backup. If Server A fails, would a failover cluster take care of the shift from Server A to B? Would it maintain user sessions, or do I need to implement NLB(s) or sticky sessions? Thanks kind people of Stack Exchange.

Answer 1

In order to preserve sessions, you will have to enable a session-persistence mechanism that is hosted off the failed server, so you need to use either a remote SQLServer database or an StateServer (an ASP Session State server). see here for the list of options: https://msdn.microsoft.com/en-us/library/system.web.sessionstate.sessionstatemode(v=vs.110).aspx

INPROC (the default mechanism) stores session in the web applications w3wp.exe process instance. If the site goes down, that information will not be available to the other server.

As for Network Load Balancing (NLB), it is a type of clustering called "High Performance", and uses both servers all the time. Fail-over clustering (called "High Availability") is distinct in that only one server is active at a time, and instead of monitoring the load on each server, it worries about Hello signals that tell the cluster the state of the primary node.