SharePoint 2013: Application error when access /...[site page] Error=Request timed out

Problem

You administrator a small SharePoint 2013 Enterprise farm having traditional topology: 1 application, 2 web front ends, 1 database server and 1 OWA.  Some users report that they can connect to the customer main website just fine.  However, when they then attempt to navigate to a specific site in that website, their browser stays busy for awhile, and then their browsers display an error message:

Sorry, something went wrong
An unexpected error has occurred.
Technical Details

You do a spot check among some users and find that some have been able to access this particular subsite, but others haven't.

Troubleshooting

1. Central Administration Health report: you find no error messages.
2. Server Event Logs: same for the WFE server event logs, no issues.  Given that some users are experiencing this issue and some are not, you suspect that the problem is occurring on just one of the two web front ends.  
3. ULS logs on both machines: you conduct searches based upon usernames and URL of the site.  On one of the WFEs, you find the following curious entries:
   

   Application error when access /.../SitePages/Home.aspx, Error=Request timed out.
   
   System.Web.HttpException: Request timed out. Getting Error Message for Exception
   
   System.Web.HttpException (0x80004005): Request timed out. Redirect to error.aspx failed.
   
   Exception: System.Web.HttpException (0x80004005): Cannot redirect after HTTP headers have been sent. at System.Web.HttpResponse.Redirect(String url, Boolean endResponse, Boolean permanent) at Microsoft.SharePoint.Utilities.SPUtility.Redirect(String url, SPRedirectFlags flags, HttpContext context, String queryString) 

4. SecurityTokenServiceApplicationPool: restarted both.  Problem still occurs.
5. IIS: performed an IISRESET on the WFE exhibiting the curious ULSlog entries.  Afterwards, all users report they are now able to access the subsite without issue.

Solution

1. Identify which WFE the issue is localized to.
2. Perform IISRESET on that WFE.

References

• None