[xvfb-plugin] fails second time

[V. Mark Lehky]

I have just installed the xvfb-plugin on my Jenkins:
- Linux jenkins 3.2.0-4-amd64 #1 SMP Debian 3.2.68-1+deb7u6 x86_64 GNU/Linux
- Xvfb Version: 2:1.12.4-6+deb7u6
- Jenkins ver. 1.641
- Xvfb plugin 1.1.2

I configured everything with defaults as per documentation.

The first time I run a job, in the logs I can see:

Xvfb starting$ Xvfb :1 -screen 0  -fbdir /var/lib/jenkins/xvfb-99-1021388786522495009.fbdir
and my job runs fine.

Every subsequent run, the logs say:
Xvfb starting$ Xvfb :1 -screen 0  -fbdir /var/lib/jenkins/xvfb-100-2665068639033469958.fbdir

ERROR: Xvfb failed to start, consult the lines above for errors

The "lines above" are just those two, nothing else. Is there a log somewhere? If I reboot the server, then I am back to "first time"; however this is a pretty drastic workaround.
What do I do to resolve this?

TIA for any advice.

[Christopher Orr]

On 10/12/15 21:19, V. Mark Lehky wrote:
> I have just installed the xvfb-plugin on my Jenkins:
> - Linux jenkins 3.2.0-4-amd64 #1 SMP Debian 3.2.68-1+deb7u6 x86_64 GNU/Linux
> - Xvfb Version: 2:1.12.4-6+deb7u6
> - Jenkins ver. 1.641
> - Xvfb plugin 1.1.2
>
> I configured everything with defaults as per documentation.
>
> The first time I run a job, in the logs I can see:
>
> Xvfb starting$ Xvfb :1 -screen 0 -fbdir
> /var/lib/jenkins/xvfb-99-1021388786522495009.fbdir
> and my job runs fine.
>

> Every *subsequent* run, the logs say:

> Xvfb starting$ Xvfb :1 -screen 0 -fbdir
> /var/lib/jenkins/xvfb-100-2665068639033469958.fbdir
>
> ERROR: Xvfb failed to start, consult the lines above for errors
>
> The "lines above" are just those two, nothing else. Is there a log
> somewhere? If I reboot the server, then I am back to "first time";
> however this is a pretty drastic workaround.
> What do I do to resolve this?
>
> TIA for any advice.

I would guess that Xvfb isn't actually getting shut down after the
initial build? Do you see it still running after a build completes?

Do you see the "Xvfb stopping" line in the output, and any other errors
around the same time?

Regards,
Chris

[V. Mark Lehky]

When it runs correctly (the first time), the last thing in Jenkins that I see is:

Xvfb stopping
Finished: SUCCESS

After a failure, I even tried `ps -ef | grep -i xvfb` on the server and got nothing.

[V. Mark Lehky]

I have just tried running Xvfb from a Pre-build script.

I first tried the same command that the plugin created, but just from command line on the server:
Xvfb :1 -screen 0  -fbdir /var/lib/jenkins/xvfb-106-4356636144193454909.fbdir
I get error:
Invalid screen configuration -fbdir for -screen 0

If I run just:
Xvfb :1 &
export DISPLAY=:1
then my tests fail with:

Error: no display specified
because, of course, there is no way to export a variable from a pre-build script.

:(

[V. Mark Lehky]

OK, I got it: I made the mistake of reading the documentation. :(
The documentation says: Xvfb screen changes the screen resolution and pixel depth, it needs to be in WxHxD format (i.e. 1600x1200x24). The default is 1024x768x24.
Unfortunately, there is no default, the default is blank, which is wrong. Once I specified something (I used "1024x768x24"), it started to work again.

On Thursday, 10 December 2015 13:19:19 UTC-7, V. Mark Lehky wrote: