A piece of good news to begin with: it is possible to perform a non-disruptive memory upgrade on one node at a time.

1. Start with a little bit of prep work.
   • Check cluster status.
   • Download and install the latest version of NCC (Nutanix Cluster Checker) and execute all health checks. Resolve any issue found.
   • Identify the node you are performing the hardware maintenance on by turning on the chassis identifier lights on the front and back of the node that you will remove using one of the following options. The lights turn on for four minutes unless you change the value.

1. Now you can migrate VMs of the node.
2. Shut down CVM and the host.
3. Replace or add DIMMs.

For detailed outline of the process please refer to KB-1623 HW: Upgrading Physical Memory