I need to install a software raid-0 array on a Ubuntu 12.04 server with
mdadm through commandline (SSH).
The drive setup is as follows:
SDA = OS SSD
SDB = HDD for raid 0
SDC = HDD for raid 0
As I understand it, it's best practice to set the drive flags as "raid" before adding them to a mdadm raid array. Okay fine, but I also heard people say that they didn't do this and mdadm worked fine. Does mdadm auto-add the raid flag once you add the drives to the array and begin building? Is there any benefit to using the raid flag since it appears mdadm seems to work with or without it?
I had a RAID 1 setup using by bios. Ubuntu was installed on the RAID array. I now want to move to a software raid using mdadm. I have deactivated the RAID 1 in the bios. I copied the operating system to a separate drive. I now want to create a RAID 5 with 3 disks. 2 of the 3 disks was previously in the fakeraid. Fdisk still shows the fakeraid and has somehow marked the raid as active.
I'm new to Ubuntu and server administration in general, but have been having good times with several Ubuntu 12.04 servers I've set up at my company.
I had believed I had properly set up a software RAID-1 array during Ubuntu installation on one server, but when I learned more about the mdadm tool, I discovered the RAID is degraded and one of the disks is "removed"
I want to kill/destroy a mdadm array and start over, as I tried to do a raid 10 and did not realize it would actually work with uneven amount of drives, I figured it would have just put 1 drive as hot spare, or build it but in degraded mode. Now I can't expand it and add the other drive. (had to RMA it). I just want to destroy and start over.