how does qualys actually logs into the system?
1. Is it an interactive login?
2. What privilege level is needed?
3. Does it perform multiple logins per scan or just 1?
Qualys's help file has a lot of advice on configurations, but none that I have seen on interactive login (https://qualysguard.qualys.com/qwebhelp/fo_portal/index.htm?#/qwebhelp/fo_portal/scans/vm_scans_lp.htm) Depending on whether or not you have the capability to change the scanner account's password without logging into it interactively, you may or may not want to keep interactive login ability (like if you can change the password in the cmd console/powershell, then you probably don't need interactive).
Domain admin level privilege is recommended, though an account with less privilege can still work - there would just be less info (I've not been able to test how much less, myself). FYI, according to Qualys the scanning account does not do any writing, only reading.
I have no idea about multi-login.
Hope this helps.
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