> Can I combine VMWare ESXi (free version) virtualization and CentOS > mdraid level 1? Any pointers how to do it? I never used VMWare before. Not if you want to run ESXi on bare metal; ESXi is an OS in it's own right. VMware Player/Server/Workstation OTOH will run on top of mdadm as it needs a host OS and doesn't care what it is given as a block device. -- Drew "Nothing in life is to be feared. It is only to be understood." --Marie Curie