Periodically receiving 502 error dialogs

[s7726]

We have the BMV up on a projector and periodically we it give an error 502 dialog that we have to click through. There seems to be no other issues, and clicking through it always results in normal operation until it comes back. We're on a small internal network that we don't notice any network interruptions on.

BMV: 1.3+build.72
Jenkins: 1.554

[jan-molak]

Hi @s7726 and thanks for your feedback. I'm on holidays right now, but will look into this in a couple of weeks when I'm back. In the meantime would you mind posting the details of the error you mentioned? They should be displayed as part of the dialog. In case they're not there (this might happen when Jenkins server returns 502 with no response body) maybe you could check you Jenkins log for any anomalies, stack traces, etc. and post them here? Thanks!

[jan-molak]

Hi @s7726, I'm closing this ticket for now as I'm not able to reproduce the issue or investigate it further without some more details.

[awlunsfo]

Also receiving 502 errors when the page tries to refresh. Nothing shows up in the Jenkins log, but the following pops up in the browser's developer console:

POST http://hostname/jenkins/ajaxBuildQueue 502 (Proxy Error) prototype.js:1585
Ajax.Request.Class.create.request prototype.js:1585
Ajax.Request.Class.create.initialize prototype.js:1550
(anonymous function) prototype.js:452
klass prototype.js:101
f hudson-behavior.js:1461

POST http://hostname/jenkins/ajaxExecutors 502 (Proxy Error) prototype.js:1585
Ajax.Request.Class.create.request prototype.js:1585
Ajax.Request.Class.create.initialize prototype.js:1550
(anonymous function) prototype.js:452
klass prototype.js:101
f hudson-behavior.js:1461

POST http://hostname/jenkins/$stapler/bound/028db951-be0e-40b5-a598-5c86a2c9a46b/fetchJobViews 502 (Proxy Error) angular-1.1.5.min.js:106
(anonymous function) angular-1.1.5.min.js:106
o angular-1.1.5.min.js:102
g angular-1.1.5.min.js:100
i angular-1.1.5.min.js:79
i angular-1.1.5.min.js:79
(anonymous function) angular-1.1.5.min.js:80
e.$eval angular-1.1.5.min.js:92
e.$digest angular-1.1.5.min.js:90
e.$apply angular-1.1.5.min.js:92
applyRootScope cron.js:15
step cron.js:29
(anonymous function) angular-1.1.5.min.js:108
e angular-1.1.5.min.js:31
(anonymous function)

[jan-molak]

Hi @awlunsfo and thanks for reporting this issue. Could you please tell me a bit more about your network configuration? Is your Jenkins behind a proxy? This stack trace does look like a genuine proxy error - neither Build Monitor nor Jenkins client can connect to the Jenkins server...
Looking forward to hearing from you.

[awlunsfo]

Yes, Jenkins is behind a proxy. The box hosting Jenkins is behind a
firewall, and we have a proxy rule that sends traffic from our company's
internal "hostname.net/jenkins" to the Jenkins box at "localhost/jenkins".
I'm not sure what other information I can give, unfortunately.

On Sat, Apr 19, 2014 at 3:37 PM, Jan Molak notifications@github.com wrote:

Hi @awlunsfo https://github.com/awlunsfo and thanks for reporting this
issue. Could you please tell me a bit more about your network
configuration? Is your Jenkins behind a proxy? This stack trace does look
like a genuine proxy error - neither Build Monitor nor Jenkins client can
connect to the Jenkins server...
Looking forward to hearing from you.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/52#issuecomment-40878562
.

[jan-molak]

This seems to be a problem with one of the components between the browser and your Jenkins server rather than the Build Monitor plugin itself. All the three errors you're seeing indicate a 502 Bad Gateway error:

• POST http://hostname/jenkins/ajaxBuildQueue 502 (Proxy Error) prototype.js:1585
• POST http://hostname/jenkins/ajaxExecutors 502 (Proxy Error) prototype.js:1585
• POST http://hostname/jenkins/$stapler/bound/028db951-be0e-40b5-a598-5c86a2c9a46b/fetchJobViews 502 (Proxy Error)

First two requests came from Jenkins itself, the third one from the Build Monitor.

502 Bad gateway usually means that your proxy (nginx, apache, etc) couldn't connect to the upstream socket. I'd suggest checking error logs on any components that exist between the browser and the Jenkins server.

Hope this helps!

[awlunsfo]

Thanks for the help! I'll dig around some more and see what I can figure
out.

On Tue, Apr 22, 2014 at 9:55 AM, Jan Molak notifications@github.com wrote:

This seems to be a problem with one of the components between the browser
and your Jenkins server rather than the Build Monitor plugin itself. All
the three errors you're seeing indicate a 502 Bad Gateway error:

• POST http://hostname/jenkins/ajaxBuildQueue 502 (Proxy Error)
  prototype.js:1585
• POST http://hostname/jenkins/ajaxExecutors 502 (Proxy Error)
  prototype.js:1585
• POST
  http://hostname/jenkins/$stapler/bound/028db951-be0e-40b5-a598-5c86a2c9a46b/fetchJobViews502 (Proxy Error)

First two requests came from Jenkins itself, the third one from the Build
Monitor.

502 Bad gateway usually means that your proxy (nginx, apache, etc)
couldn't connect to the upstream socket. I'd suggest checking error logs on
any components that exist between the browser and the Jenkins server.

Hope this helps!

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/52#issuecomment-41041985
.

[jan-molak]

No worries, good luck!

[awlunsfo]

After looking around for suggestions to fixing Jenkins proxy issues, I came
across someone who suggested adding this line to my httpd.conf file:

SetEnv force-proxy-request-1.0 1

...and it worked! Problem solved. More info about that flag can be found
here:

http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#envsettings

On Tue, Apr 22, 2014 at 10:05 AM, Jan Molak notifications@git.luolix.topwrote:

No worries, good luck!

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/52#issuecomment-41043171
.

[jan-molak]

Excellent! Thanks for posting the solution :-)