No Requests are sending and No Actions are Performing on HTTP-Host Target URL from AWS Linux Machine

As I am able to run my Framework with No issues in my windows using the target URL,

But the same target URL is not working in the AWS Linux Machine, getting the HTTP Response as 0, please find the Attachment below,

Here, I am running my Framework on windows as MasterController and AWS Linux Instance as AgentController, on running the Framework, I am able to fetch the AgentControlller and also able to ping the target URL, but no Requests are sending and no Actions are Performing, please check the attached file.

Please suggest do we need to configure any settings regarding HTTP or we need to install any other API’s.

Response code 0 indicates that no response was received for the request. Please have a look at the Errors page of the load test report you have created. It should give some indication what went wrong when sending requests to that host.

Thanks for your info,

On Error Page getting the exception as- Could not initialize class com.xceptance.xlt.engine.socket.InstrumentedSocketImpl
Please check the attached file and please suggest, how to overcome this exception.

Ah, that’s interesting. Please let me know which version of Java you are using on the AWS Linux machine and I will try to reproduce that issue.

Meanwhile, please disable socket instrumentation altogether by setting the following property in the configuration of your test suite, for example in file “”:

com.xceptance.xlt.socket.collectNetworkData = false

java version “16” 2021-03-16
Java™ SE Runtime Environment (build 16+36-2231)
Java HotSpot™ 64-Bit Server VM (build 16+36-2231, mixed mode, sharing)

Thanks! I will get back to you when I have more intel.

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Looks like this exception is caused by an incompatibility of XLT and Java 16. We could reproduce it and will fix it soon. See for more info. Many thanks for making us aware of this issue!

Until a fix is released, there are two workarounds. First check if you really need network timing data: connect time, time to first bytes, etc. See the Network Timings tab on the Requests page of the load test report for the available values. If you don’t need that data in the moment, disable the collection of this data as described above and stay with Java 16. If you need that data, you would have to downgrade Java to version 15 on your AWS machine.

Thank you @jwerner for your support and response, we were glad to have such support. :smile:

Please let us know when you release a fix to the issue.

Hi vishnu3948,
XLT 5.4.0 is available now. This version contains the fix for the issue with Java 16. See for download and release notes.
Thanks again for reporting this issue!

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