Archive

Archive for March, 2015

RAID Mayhem in Linux Mint 17.1 and Kubuntu 14

March 11th, 2015 No comments

I have a Quad-core machine that has 2+2 1TB disks configured in RAID 1+0 mode (mirror + stripe).  I am having a 64Gb SSD, on which I have the operating systems installed.  Recently, I wanted to install Linux Mint 17.1 on the SSD.  The installation went fine, but after rebooting the RAID device was not visible at all.  To overcome this problem, I had to do “dmraid -ay” to activate the RAID device in my machine.

Ok, now my RAID device is visible.  Went ahead to create /home and /data partitions, followed by updating the same in /etc/fstab for auto-mounting during boot-up.

To my surprise, the reboot failed saying /home is not ready.  Checked into recovery mode by punching in the root password and found that the RAID device has gone missing now.   Ran “dmraid -ay” again to activate the device; following by running “mount -a” make /home and /data partitions come alive.  Exited the recovery mode to complete the full booting.

Did some internet search for how to activate the RAID device on booting automatically.  It was awful that there are no direct methods to do so.   Infact, some people have advised about not rebooting the machine at all..  Funny!

Later, found a workaround, where the /etc/fstab entries were made “noauto”.  And RAID activation happening in /etc/rc.local.

/etc/rc.local

dmraid -ay
mount /home
mount /data

/etc/fstab

/dev/mapper/pdc_cjcdcdeide6    /home ext4    defaults,noauto     0   2
/dev/mapper/pdc_cjcdcdeide5    /data ext4    defaults,noauto     0   2

Moral: Never install the Operating System on a RAID device, as majority of the distributions don’t recognize them by default.  Interestingly, Fedora 21 recognized RAID during installation itself, but I ended up hating it, when I found “yum update” not working out of the box.

Tags: