Hi Guys, i'm stuck at a weird problem. I use IIS for almost 5 years, but this strangs IIS/Application behavior has never occured to me.
Infrastructure.
-Dedicated Webserver IIS 7.5
-Dedicated SQL Server 2008 r2.
-Cisco ASA in front of the webserver with HTTP Filtering.
IIS Info
- 4 Websites build in ASP.net 2.0/4.0
- Maximum of concurrent HTTP Reqests to the IIS Server 180/sec
Problem
A few times during a working day the webserver hangs, and does not serve any content, after a few minutes, the pages are being served, resulting in no errors in the log or whatever. Our external monitoring service detects this problem, cause requests are taking longer than 20 seconds.
The content is served out of the database, but also static content (an image) from the webroot directory itself. Server has normal performance monitor, and is accesible over RDP. After recycling the application pool everyting works again. So i'm assuming this will be an application related problem. Even requesting only an image of 1kb cannot be served during such an outage.
Done so far
-Recycled application pool
-uninstalled antivirus product
-rebooted server
How to troubleshoot this problem?