Thanks for contacting us.
Let me try to dig into your questions:
1. What do you mean by load tests to be "cloud-based"? Load tests, themselves, are stored locally, in your project folder. They can capture and measure traffic from any web site, be it intra- or internet-based. You can check out the "Caution" section in the Overview page of the documentation here
2. If you decide to use 5k VUs, it would be enough to capture only one single login traffic (see here
) and assign that capture the required amount of virtual users - its workload (here
3. When it comes to uniqueness of virtual users, data-driven load tests come quite handy. You can check this article
in the help pages.
I hope things are a bit clearer than before.
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