I have an ASP.NET MVC web application that was working great under four worker processes (web garden) configuration and using ASP.NET State service to manage incoming sessions.
Session state is configured in Web.config configuration file as below:
<system.web>
<sessionState mode="StateServer" stateConnectionString="tcpip=127.0.0.1:42424" timeout="360" />
</system.web>
No machineKey is configured in web.config configuration file and ASP.NET State service runs using the default Network service account.
Additional web server (this is a VMWare virtual machine) details are:
- IIS 8.5.9600.16384
- Windows Server 2012 R2 Standard 64-Bit
- 48GB RAM
Regarding to application pool configuration, some to highlight are:
- 32-Bit application enabled
- Integrated mode and onDemand startup
- Load user profile enabled
- Idle Time-out Action set to suspend
- Rapid fail protection enabled
- Recycling disabled and all limits disabled (set to 0)
Furthermore, Application Pool has always been configured using a custom domain administrator account but currently it has been changed to use a custom non-administrator account due to security reasons.
After changing application pool account, Web Garden has started to behave unstable: users get kicked off randomly. They are getting 403 Unauthorized and 404 Not Found http errors and even I remember to see 503 Service Unavailable.
What can be the cause?
UPDATE 2020-11-11:
