Selenium Grid CLIENT_GONE caused by Firefox 35.0.1 Cisco OpenH264 Codec Download?

[Daniel Cadden]

Hi,

We regularly run a suite of tests against our web applications using multiple Firefox Instances.

We are using four linux hosts, each running multiple X window sessions. In total, we are running up to 32 Firefox instances.

Occasionally we get CLIENT_GONE exceptions. I've done a number of packet captures to try and determine what the problem is and quite often I see that Firefox is downloading the Cisco OpenH264 Codec plugin that is uses to play video in the browser.

To try and resolve this problem, I have created a new profile in which the Open H264 plug-in is disabled.

However, because this appears to be a default Firefox plugin, I believe that Selenium Server overwrites the user preferences with Firefox's default preferences and the plug-in is once again enabled. I have confirmed this by seizing the browsing during the test and indeed I see the plugin has been downloaded and installed.

It's hard to pin point this as the actual cause of the problem, but it's possible to see how this could be giving rise to it. The CLIENT_GONE exceptions always correlate with a time out on page load which is recorded in the Selenium node logs. I suspect the bandwidth used to download the codec multiple times, combined with the sometimes dubious quality of our ADSL is prolonging page load times, occasionally beyond the sixty second time out.

It would be lovely if we were able to properly disable the plugin. We are considering a couple of options - one to make amend the selenium-server source code so that the codec is disabled in the copied Firefox profile - it could be enabled with a paramater? Subject to reception of the idea, it could be contributed back to "trunk". Alternatively, we could stage a local download of the Codec using amended local DNS records. Or we could use an older version of Firefox that doesn't download this Codec as a Plugin.

I'd really appreciate some feedback before we decide on how we can remedy this. It would also be great to hear from anyone experiencing similar issues.

Thank you

Daniel

​

Codeweavers April Newsletter l Benefits of upgrading to Codeweavers latest online finance solution



Codeweavers Ltd | Barn 4 | Dunston Business Village | Dunston | ST18 9AB
Registered in England and Wales No. 04092394 | VAT registration no. 974 9705 63 

Phone: 0800 021 0888  Email: contactus@codeweavers.net

[Krishnan Mahadevan]

Daniel,

To the best of my knowledge, Selenium/WebDriver should just use the firefox profile that you are providing to it and not resort to doing anything else. Since the firefox profile is going to be part of your test, when you work with the Grid, it basically gets shipped over to the actual node that is going to be running your test and the node uses the provided profile to spawn firefox.

Thanks & Regards
Krishnan Mahadevan

"All the desirable things in life are either illegal, expensive, fattening or in love with someone else!"
My Scribblings @ http://wakened-cognition.blogspot.com/

My Technical Scribbings @ http://rationaleemotions.wordpress.com/

Phone: 0800 021 0888  Email: cont...@codeweavers.net

--
You received this message because you are subscribed to the Google Groups "Selenium Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email to selenium-user...@googlegroups.com.
To post to this group, send email to seleniu...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/selenium-users/54d1bc15-f1ba-4b78-931f-8f67b9cf2e10%40googlegroups.com.
For more options, visit https://groups.google.com/d/optout.