Configuring RAIDwith mdadm

Raid ?

Redundant Array of Inexpenisve Disks JBOD Raid 0,1,2,3,5,6 Combinations 10,0+1, etc ...

Raid0

Striping Non-redundant Focus on speed Multiple disk balance the load 1 disk broken = All data gone

Raid 1

Mirroring Data is replicated to 2 or more disks 1:1 ratio realtime backup Slow Minimum of 2 disks

Raid5

Striped set with distributed parity or interleave parity requiring 3 or more disks

Size = n disks – 1 Data is not destroyed if one disk is lost Due to parity recalculation the spare can

be rebuilt

Raid 6

Striped set with dual distributed parity Becomes more important Can recover diskfailures up to 2 drives Important while rebuilding large drives

Raid-combinations

Raid 1+0 = Mirror of striped sets (Raid10) Raid 0+1 = Striping of mirrors

Comments

RAID is NOT backup !!! Keep rsync or cold backups !

Hot spare Software Raid vs Hardware Raid Detailed information on next url :http://nl.wikipedia.org/wiki/Redundant_Array_of_Independent_Disks

Installation

Follow normal installation steps until you get to the partitioning wizard

There you choose manual partitioning

Repeat partitioning

Repeat slides 6 through 12 to complete the partitioning scheme

The result should be as the following slide

Finish MD configuration

Repeat slides 16 through 20 until you get the result on the next slide

You will notice when you’re finished with designating MD devices, when you have selected all pairs

Then select “Finish”

Finish installation

Continue finishing your installation if it were a normal one

Refer to semester 1 documentation if necessary

MDADM

Once rebooted on your new system, install mdadm raid tools

Apt-get update && apt-get install mdadm Mdadm - -detail /dev/md? Cat /proc/mdstat dmesg