I updated the apache config file with the fix given here:
I added this in on Wednesday, and have checked various gateway quiz assignments that have been generated since then. At least for the two dozen or so assignments that I have checked, there have not been any repeated seeds in the fashion that was happening before. So, I am cautiously optimistic that this has fixed the issue for us.
WeBWorK Main Forum
Issues with gateway quizzes generating with the same seeds
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