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Use a different display argument if :20 is not available.
$ cd /path<INSTALL>/to/soatest/plugins/com.parasoft.xtestptest.libs.web_[version]<VERSION>/root$ ./Xvfb_Linux :20 -ac
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Once you determine the arguments that you need to pass to Xvfb, put these arguments to use in SOAtest. To do so, create a shell script named Xvfb_Linux that invokes Xvfb with the necessary arguments. SOAtest will then run the shell script when trying to start Xvfb.
(1) In /path/to/soatest/plugins/com.parasoft.
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ptest.libs.web_
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<VERSION>/root rename Xvfb_Linux to Xvfb_Linux.bin.
$ mv Xvfb_Linux Xvfb_Linux.bin
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