[SOLVED] 1TB software RAID 5 with one hot spare.

[Impotence]

I have been putting this off for a month, due to worrying too much about doing it wrong... i would appreciate it if someone would take me through this step by step.

Distribution

• Kubuntu 8.04 KDE4 remix (x86)

Hardware

• 3 x 500GB SATA drives (sdc,sdd and sde) [unformatted, unmounted] to be RAID 5'd.
• 1 x 500GB SATA drive (sdb) [ext3, /home, 99% full] for a hot spare.

The hot spare drive cannot be added until the array has been built as i do not have anywhere to store its contents (and the raid has been tested to death, I'm not wanting to loose 430GB of data!)

What i have done so far

• Tied up SATA data & power cables to stop them from moving
• Used hot glue to prevent sata data & power connectors from coming lose from HDD / Motherboard
• Installed mdadm

What i need to do (help!)

• Create the RAID
• Setup RAID monitoring [audible alarm if a disk dies]
• create a lvm on it
• format the lvm (Suggestions? something journaled?)
• Create test data on the RAID (a copy of /home)
• Selectively drop individual disks out of the array (can't unplug them, dban them?) and learn to rebuild it.
• when i am confident that it is 'stable' mount it as /home
• Add the old /home disk (sdb) to the array as a hot spare
• Possibly use sdb to make a 1.5TB raid once i have filled 1TB (for future reference)

Questions

• If i change distribution / when i do a clean install, how do i mount the raid? what files (if any) do i have to have a copy of to do it (such as the mdadm config file?)

[Impotence]

I have managed to do it myself, my thanks to anyone who took the time to read my post but where unable to help.

I am currently writing up what i have learned in the form of a idiot proof distribution independent tutorial... I will post a link when it is complete.

I also plan to fill in https://wiki.ubuntu.com/LVMOnRaid when i have finished!

[flatline]

Have you written up your guide yet? I just found this post and am interested in your findings. I currently have a RAID1 setup that I would like to add a hot spare to using mdadm, and I also need to setup monitoring - specifically, I need it to send me an email if the array has a disk failure.

Also - is your OS/bootloader on the RAID5 array? I was just told that you cannot boot from a software RAID5 array.

Thanks!