"unknown-sdk" device when executing tests in Jenkins

Question

I have a strange situation with Jenkins when trying to run the tests.

The configuration of the job clearly specifies to run the tests on this specific avd: "hudson_en-US_160_HVGA_android-18_armeabi-v7a", but for some odd reasons, during the build process, 2 devices are found. One of the devices is the previous one, but the other is called "unknown-sdk".

The tests are successfully executed on the specific avd, and fail on "unknown-sdk":

The relevant portion of the log:

[SR.runTests] Executing instrumentation suite on 2 device(s).
[SR.runTests] [emulator-8215] Starting execution.
[SR.runTests] [localhost:8216] Starting execution.

Running am instrument -w -r -e class com.smoke.tests.LoginTest com.muume.dev.test/android.support.test.runner.AndroidJUnitRunner on unknown-sdk-localhost:8216

2015-06-17 11:54:05 [SDR.printStream] [localhost:8216] STDOUT 11:54:05 I/InstrumentationResultParser: test run failed: 'Unable to find instrumentation info for: ComponentInfo{com.muume.dev.test/android.support.test.runner.AndroidJUnitRunner}

As you can see, it detected 2 devices: emulator-8215 which is the known avd, and localhost-8216 which is the unknown and causes the problems.

My question is how to restrict the tests to run only one single emulator, and from where did the "unknown-sdk-localhost" comes from.

Answer 1

"unknown-sdk" is what it tells adb while the emulator is still busy loading itself.