RAID-1 configuration on 4 Hard disks
 

Hi guys,
I need to configure RAID-1 on a system having 4 Hard disks each of 300GB.

Scenario:
There are 4 Hard disks and i have to configure RAID1 for HD1&HD3 and HD2&HD4.

Now, can you please explain me how to do the whole setup/configuration including RHEL6 OS installation on the system In This Scenario.

Lets say there are 4 HDs i.e. sda1, sda2, sda3, sda4.
Now, on which HD, i will install the OS ?
Where should i install the /boot ? on sda1 ?
As i know /boot cant be on RAID but / and SWAP can be on RAID.

If i install the OS on HD1(sda1), then how i am gonna create the RAID of HD1&HD3 and HD2&HD4 coz in this case OS installation itself will take some space to install.

FYI:
I know how to configure RAID 1. I have done it before. I am only having problem in understanding this particular scenario.

Please tell me if you guys need some more information.
Thanks

You may find these useful
http://www.linuxtopia.org/online_boo...oning-x86.html
http://www.linuxtopia.org/online_boo..._RAID-x86.html
http://linux.die.net/man/8/mdadm

Note that you are confusing disks with partitions eg if you have 4 disks, they will likely show as sda, sdb, sdc & sdd.
The first 3 partitions on sda would be sda1, sda2, sda3.


HTH

each pair of drives need to be configured as separate raid volumes, you'll have two(2) separate arrays. so, you'll need to set up arrays twice...

one thing you might find useful is to set them up, instead of using /dev names, use uuid, then they can be plugged in totally different drive controller connectors, yet still work.

/boot can be on raid 1 and you first create the raid arrays and then install the OS.

With grub2 (now default in any recent version of all distributions), you can in fact have /boot on RAID. And also, I would suggest to look into LVM. You can set up 2 RAID1 arrays as Physical Volumes, merge them together into one Volume Group and create Logical Volumes for root, home etc. In most cases, you can boot from a Logical Volume on RAID1 just fine.