I'm deploying 4 Nutanix blocks for my customer. They are a security conscious company so changing the IPMI/ESXi/CVM passwords was a given after the install completed. We've experienced no end of issues after changing the passwords and now have a support call open to try and get the issue resolved. Don't get me wrong, the support is good, but I get the impression changing the passwords is something of an unknown. I'd be interested to hear other people's experiences.