Memory hot add lets you add memory resources for a virtual machine while the machine is turned on.

Enabling memory hot add produces some extra memory overhead on theESXi host for the virtual machine.

Power off the virtual machine.

Ensure that the virtual machine has a guest operating system that supports memory hot add functionality.

Ensure that the virtual machine compatibility is ESXi 4.x and later.

Ensure that VMware Tools is installed.


Right-click the virtual machine and select Edit Settings.


To locate a virtual machine, select a datacenter, folder, cluster, resource pool, host, or vApp.


Click the Related Objects tab and click Virtual Machines.


On the Virtual Hardware tab, expand Memory, and select Enable to enable adding memory to the virtual machine while it is turned on.


Click OK.