Not sure what you expect. Hangstop booting and DNS issues is so vague, could you provide more details? What happens exactly and how do you fix it usually? Any logs you can provide? What OS is running on the VMs?

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I’m almost 100% sure you’re hitting some kind of HDD or SSD cache as you mentionned. Setting up an iperf test between your file server and windows machine should give you a good hint on where the issue lies.