Deploying MVC 6 website to Azure results in error 502

Question

I used to have no problem with deploying my asp.net 5/mvc6 website to my Azure apps/website environment, but last months I'm having weird issues.

If I deploy my website to Azure, 90% of the times, the browser will be opened automatically when the deploy succeeded, and it will just load for 5 minutes and eventually will give me a 502 error or a 500 error for timeout. I can redeploy many times but it will never work. I can't pinpoint the difference between a basic empty website and my website because the empty template website will initially work, but if I make some changes to it inline with my problem-website it will give the error, but then when I revert all changes the problem persists even with a empty 'hello world' website.

None of the code will ever be reached to remote debugging is useless, the problem happens in the startup of the app it seems.

update

From what I can tell so far is that it seems be related to the solution, since the same project does work in a new/empty solution. I have a basic Soluion Items/src/test/tools folder structure, with a global.json and .tfignore in the Solution Items. (tried deleting global.json but didnt make a difference)

The eventlog.xml gives me

View Msvsmon's help for more information.</Data><Binary>08005E80</Binary></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T18:40:24Z"/><EventRecordID>1002678312</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '6424' failed to start. Port = 11271, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T19:40:29Z"/><EventRecordID>1006283437</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '9840' failed to start. Port = 20348, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T20:40:41Z"/><EventRecordID>1009895484</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '9796' failed to start. Port = 27433, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T21:40:56Z"/><EventRecordID>1013510812</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '7748' failed to start. Port = 33738, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T22:41:16Z"/><EventRecordID>1017131093</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '5844' failed to start. Port = 20405, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-15T23:41:43Z"/><EventRecordID>1020757406</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '4208' failed to start. Port = 16859, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T00:42:13Z"/><EventRecordID>1024387796</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '8840' failed to start. Port = 23996, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T01:42:48Z"/><EventRecordID>1028023000</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '8724' failed to start. Port = 9206, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T02:43:29Z"/><EventRecordID>1031663140</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '320' failed to start. Port = 9307, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T03:44:14Z"/><EventRecordID>1035308281</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '9540' failed to start. Port = 27060, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T04:44:14Z"/><EventRecordID>1038908703</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '8212' failed to start. Port = 31282, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T05:44:20Z"/><EventRecordID>1042514234</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '9608' failed to start. Port = 23608, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T06:44:30Z"/><EventRecordID>1046124390</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '4216' failed to start. Port = 15739, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T07:44:45Z"/><EventRecordID>1049739625</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '3544' failed to start. Port = 13495, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T08:45:05Z"/><EventRecordID>1053359796</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '908' failed to start. Port = 6457, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T09:45:30Z"/><EventRecordID>1056984968</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '5272' failed to start. Port = 32023, Error Code = '-2147023829'.</Data></EventData></Event><Event><System><Provider Name="HttpPlatformHandler"/><EventID>1000</EventID><Level>0</Level><Task>0</Task><Keywords>Keywords</Keywords><TimeCreated SystemTime="2016-05-16T10:46:01Z"/><EventRecordID>1060615265</EventRecordID><Channel>Application</Channel><Computer>RD0003FF1D2CD5</Computer><Security/></System><EventData><Data>Process '7708' failed to start. Port = 9729, Error Code = '-2147023829'.</Data></EventData></Event></Events>

My web.config are default.

 <handlers>
      <add name="httpPlatformHandler" path="*" verb="*" modules="httpPlatformHandler" resourceType="Unspecified"/>
    </handlers>
    <httpPlatform processPath="%DNX_PATH%" arguments="%DNX_ARGS%" stdoutLogEnabled="false" startupTimeLimit="3600"/>

Answer 1

That looks like you may hit some limits about timeout or different related issue. And performance, for sure. Try to move your web app to more powerful mode like a standard and see if that will help. Next, it is not so simple to say the reason of 500/502. There is the official guidance for troubleshooting these errors.

I would start with enabling a verbose diagnostics as described here and here and see if you have any things going on in the logs. Also, some logs are available through the Kudu console ( http://webappname.scm.azurewebsites.net , note SCM) in the Debug console in the LogFiles console.

Answer 2

After completely recreating my solution in a 2nd test-solution, and adding in projects and references step by step and trying to find the breaking point, I noticed that when I added another class lib (quite a large one) to the solution and reference it from my MVC6 app it would break. If I would then remove the reference it would still be broken so it seemed like a unfixable issue. After some trial and error's I started messing with the references in the packages and wrap-folders, and eventually found the issue.

By default the asp.net libs use an embedded Newtonsoft.json version 6.xxx. I added the latest version of Newtonsoft.json (8.xx) to my MVC 6 project, then deleted the (old) newtonsoft folders/files from the wrap and packages folder.

Also changed to DNX46 instead of 451 (tried that before, but didnt make a difference regarding the issue).

The build would break initially after deleting the 6.xxx files but rebooting Visual Studio will fix this.

After these steps I deployed to Azure and everything worked. I tried this fix in multiple solutions now that had the exact same issue and it seems to be a solid fix.

It could be that there is something in my referenced class lib that is causing this versioning issue since creating a new solution with blank class libs/mvc projects will work fine, but either way I'm glad this is resolved.