Hi All,
I am looking at getting our IIS server in a failover state, however as we use many websites that use session states and cookies we can't currently use NLB (without refactoring the apps to use SQL for session storage... I'll come back to this in a sec). Here's the scenario we'd like:
WEB1 is the primary web server
WEB2 is the secondary web server (identical config & content)
Example: One day, WEB1 goes down (i.e. will not serve HTTP requests). All traffic should automatically failover to WEB2. We will handle individual site/appPool errors ourselves, we only want it to failover in the event of OS/network/W3SVC problems. Ping/heartbeat is a good indication.
I found a way to do this manually with NLB (by setting WEB2 to 0 share so no requests go to it) but we'd like it to happen automatically. If this can be done with NLB, there's a chance I can persuade our devs to use SQL for sessions instead.
This presents a couple of questions though:
1) If the NLB host goes down; requests can't be answered - correct? How do you mitigate against this single point of failure? If it's not doable, surely that means no improvements have been made because it's still putting all our eggs (websites) into one basket?
2) I've looked at this which is quite complex... we'd need a LOT of scripts to do this for all our sites. Has anyone used it and more importantly - do you recommend it?
Thank you very much for any assistance or advice with this!
Brad
(Windows Server 2008 R2 / IIS 7 / Server 2008 Domain)