Hello, do you know if we can have impacts on Citrix CVAD /Daas Farms with MCS and PVS if we disable LLMNR with GPO ? Thank you

MCS would not be affected as it's local reads/writes and doesn't involve any network traffic. As far as I know PVS reads/writes are all IP based, from the boot sequence onwards so with no name lookups required should not be impacted. Other non-PVS VDA traffic outside could be impacted of course. https://support.citrix.com/s/article/CTX227725-citrix-provisioning-services-boot-process?language=en_US