Every time I have to setup a software RAID in Linux using mdadm I forget something, this time I am writing it down once and for all (or at least I hope so). For the sake of simplicity I will use the creation of a RAID1 as example but this very same procedure can be applied for any other kind of RAID. RAID array creation 1. Partition the drives This step must be repeated for each drive of the array (/dev/sdb and /dev/sdc in my case). …

XenServer, like many other bare-metal hypervisors, only supports a small bunch of RAID controllers. The difference between it and for example VMware ESXi is that XenServer is pretty much a CentOS minimal install with some proprietary administration tools and a pretty decent remote manager (only for Windows as long as I know…) while ESXi is a completely proprietary closed source blob. XenServer being based on CentOS makes it possible to do many weird unsupported things, like installing it on a software fake RAID on ICH8R. To install it on a software RAID1 all we have to do is perform the usual installation (without configuring any local storage) on a single HDD (/dev/sda), copy everything on a second drive (/dev/sdb) and use mdadm to build a couple of RAID volumes. – I’m pretty much only reposting things I read somewhere, I don’t take any credit for this guide – …