We have a webfarm with 3 web servers all in windows server 2008 r2. One of our servers has some hardware issues and we are looking to get a new server to replace it, however it is actually cheaper to get a server with a more memory which actually requires a new OS - windows server 2012 r2.
If we got a new box with the windows server 2012 it would mean running IIS 8.5 on the new box, and 7.5 on the 2 older boxes. Can you have a webfarm in this sort environment and keep the "Shared config" setting in IIS? Or is it best to get an old box, or (even more painfully) attempt to update all 3 servers?
