Disk partitioning for Linux (iii)

Raid

Redundant array of Inexpensive disks

Redundant Arrays of Inexpensive Disks

Different levels of RAID capabilities and features vary

Compare items	RAID0	RAID1	RAID10	RAID5
Number of disks	>=2	>=2	>=4	>=3
Storage utilization	100%	50%	50%	N/n-1
Redundant check disk	0	0	0	1
Disaster tolerance	0	1	1	1
IO performance	High	Low	In	Higher

• RAID0 is a parallel write disk with the highest IO performance, but no disaster tolerance
• RAID1 is 1 disk write 1 disk to do backup
• RAID10 is a combination of RAID0 and RAID1.
• RAID5 is a parallel storage data, 1 disk has to do the test bit, can reverse the introduction of another disk of data

"Raid Experiment"

1. Prepare 5 pieces of 20G size hard disk

2. Create RAID0 using SDD and SDE two disk

[[email protected] ~]# mdadm-c/dev/md0-l0-n2/dev/sd{d,e}1/dev/md0 started.

3. View the RAID information created

[Email protected] ~]# mdadm-d/dev/cat /proc/mdstat

4. Create File system

[Email protected] ~]# mkfs.ext3/dev/md0

5. Create a directory and mount it

mkdir -p/data/Mount /dev/md0/data/raid0/

"RAID Experiment II"

1, create RAID1 use 2 disk to do RAID 1 disk to do hot backup

[Email protected] ~]# mdadm-c/dev/md1-l1-n2-x1/dev//dev/md1 started.