If I've already created the Operating system on a Dell PowerEdge R620 server, which has 2 disks and I know that the OS is on one of the disks and I know the disks are RAID0. Is it possible to create a RAID 1 array with the 2 disks and still have the OS running, after booting up. Will the data be deleted, if I try and create the RAID 1 array.
If they are both RAID 0's now, yes, you can convert them to a single RAID 1. You must delete the RAID 0 with the disk that does NOT contain the OS, then you need to do a "reconfigure" to RAID 1, adding the no-non-RAID disk. This is all done from OMSA in the OS. It will all happen while the system is live and online.
Reconfiguration options are discussed in the storage management manual under the virtual disk section:
You can reconfigure a RAID 0 to a RAID 1, but there are limitations. A RAID 1 is two physical disks, so you can't reconfigure a 2 drive RAID 0 to a RAID 1 because you will have a disk of data that the controller will have nowhere to place.
Dell EMC, Enterprise Engineer
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