Web Farm Application deployment best practices

We are having a web farm which hosts multiple ASP.Net applications. We typically have 4 servers on the farm.

The dilemm开发者_StackOverflow社区a which i am having is in terms of capacity issue of the farm. Lets say i have currently got 200 apps in total. Should I deploy all 200 apps on all 4 servers (i.e. all the servers in the farm are identical) or should i split the applications between 2 sets of server and create 2 smaller farms so that i can then manage the application based on its criticality and usage etc.

This also depends on how many servers are needed to handle each application, and on your approach to updates.

If an app requires two servers to handle the load, then you might think you can split the apps in the way you describe. But if you need to maintain full service during upgrades, you need a third server (this is N+1 redundancy) to ensure two are always up to handle the load.

Because of things like this, I would deploy all applications on all servers, and use the load balancers (assuming you have them) to handle tha actual distribution of load across the servers. This lets you give premium apps (or even premium users) more of the available resources most of the time, but lets you re-allocate for periods of peak load, updates etc.

You should probably ask this question on webmasters.stackexchange.com too