====== RAID ======
Dokumentasi seputar RAID lengkap kami tulis disini
===== - Membuat RAID 1 SDC & SDD =====
Membuat raid array full size dan berikut ini tahapannya
==== - Format Hardisk ====
fdisk /dev/sdc
ikuti opsi ini
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-8910, default 1):
Using default value 1
Last cylinder or +size or +sizeM or +sizeK (1-8910, default 8910): ( langsung enter apabila full size )
Kemudian tampilkan hasilnya
Command (m for help): p
Disk /dev/sdc: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x000923aa
Device Boot Start End Blocks Id System
/dev/sdc1 1 30401 244196001 83 Linux
Aktifkan partisi sebagai Raid Auto Detect
Command (m for help): t
Selected partition 1
Hex code (type L to list codes): fd
Changed system type of partition 1 to fd (Linux raid autodetect)
Command (m for help): p
Disk /dev/sdc: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x000923aa
Device Boot Start End Blocks Id System
/dev/sdc1 1 30401 244196001 fd Linux raid autodetect
Partition 1 does not start on physical sector boundary.
Lakukan hal yang sama seperti diatas pada SDD
==== - Buat RAID Array ====
Lihat dulu partisi array yang ada pastikan jangan sampai bentrok
cat /proc/mdstat
hasilnya
Personalities : [raid1]
md1 : active raid1 sda3[0] sdb3[1]
306880 blocks super 1.1 [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1]
614336 blocks super 1.0 [2/2] [UU]
md127 : active (auto-read-only) raid1 sda4[0] sdb4[1]
2826812224 blocks super 1.1 [2/2] [UU]
resync=PENDING
bitmap: 22/22 pages [88KB], 65536KB chunk
md2 : active raid1 sdb2[1] sda2[0]
102334336 blocks super 1.1 [2/2] [UU]
bitmap: 1/1 pages [4KB], 65536KB chunk
anda bisa menggunakan misalnya md3 caranya
mdadm --create /dev/md3 --level=1 --raid-devices=2 /dev/sdc1 /dev/sdd1
dan pantau perubahannya
watch cat /proc/mdstat
dan hasilnya
Personalities : [raid1]
md3 : active raid1 sdd1[1] sdc1[0]
244064896 blocks super 1.2 [2/2] [UU]
[======>..............] resync = 34.6% (84689728/244064896) finish=19.7min speed=134492K/sec
bitmap: 2/2 pages [8KB], 65536KB chunk
md1 : active raid1 sda3[0] sdb3[1]
306880 blocks super 1.1 [2/2] [UU]
md0 : active raid1 sda1[0] sdb1[1]
614336 blocks super 1.0 [2/2] [UU]
md127 : active (auto-read-only) raid1 sda4[0] sdb4[1]
2826812224 blocks super 1.1 [2/2] [UU]
resync=PENDING
bitmap: 22/22 pages [88KB], 65536KB chunk
md2 : active raid1 sdb2[1] sda2[0]
102334336 blocks super 1.1 [2/2] [UU]
bitmap: 0/1 pages [0KB], 65536KB chunk
==== - Mengganti Hardisk RAid ====
Apabila anda sudah menambahkan hardisk baru /dev/sdb maka cara menambahkan hdd tsb ke raid adalah sbb
Anda tidak perlu melakukan partisi satu per satu, untuk membuat partisi /dev/sdb sama dengan partisi /dev/sda anda bisa menggunakan perintah sfdisk berikut ini
sfdisk -d /dev/sda | sfdisk /dev/sdb
Selanjutnya lihat hasilnya dengan
lsblk
setelah anda yakin partisinya sama, selanjutnya tambahkan ke raid, misalnya
mdadm --manage /dev/md0 --add /dev/sdb1
lakukan sesuai dengan partisi yang ada dalam raid.
==== Menghapus Raid ====
Berikut ini tahapan menghapus raid
mdadm --stop /dev/md1
lalu
mdadm --remove /dev/md1
jika anda mendapati error
mdadm: error opening md1: No such file or directory
maka lakukan
mdadm --zero-superblock /dev/sdf1 /dev/sde1
sesuai disk raid anda
==== Mengaktifkan dan Mendisable Raid ====
mdadm --manage /dev/md1 --fail /dev/sdb2
baru ini
mdadm --manage /dev/md1 --remove /dev/sdb2
mengaktifkan kembali
mdadm -a /dev/md1 /dev/sdb2
==== Menghentikan Raid Sync ====
echo "idle" > /sys/block/md0/md/sync_action
===== - Referensi =====
- http://www.cyberciti.biz/faq/centos-redhat-rhel-linux-setup-create-raid1/