how to configure raid 5 in redhat linux server
Hii guys today we will discuss about RAId5 .RAID 5 is a method of storage management in linux server. In this article we will learn how to configure RAID 5 in linux server if u want to know what is RAID? and what is RAID 0 RAID1 so click on my link and visit What is raid 0 ? and how to Configur in redhat linux server What is raid 0 ? and how to Configur in redhat linux server
basically RADID 5 in required 3 heard disk if one is crashes then other disk will be take place automaticly .
So lets go through the steps to configure raid level 5 in linux server
[root@localhost ~]# fdisk /dev/sda The number of cylinders for this disk is set to 4177. There is nothing wrong with that, but this is larger than 1024, and could in certain setups cause problems with: 1) software that runs at boot time (e.g., old versions of LILO) 2) booting and partitioning software from other OSs (e.g., DOS FDISK, OS/2 FDISK) Command (m for help): m Command action a toggle a bootable flag b edit bsd disklabel c toggle the dos compatibility flag d delete a partition l list known partition types m print this menu n add a new partition o create a new empty DOS partition table p print the partition table q quit without saving changes s create a new empty Sun disklabel t change a partition's system id u change display/entry units v verify the partition table w write table to disk and exit x extra functionality (experts only) Command (m for help): p Disk /dev/sda: 34.3 GB, 34359738368 bytes 255 heads, 63 sectors/track, 4177 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sda1 * 1 3315 26627706 83 Linux /dev/sda2 3316 3697 3068415 82 Linux swap / Solaris /dev/sda4 3698 4177 3855600 5 Extended /dev/sda5 3698 3722 200781 fd Linux raid autodetect /dev/sda6 3723 3747 200781 fd Linux raid autodetect Command (m for help): n Command action l logical (5 or over) p primary partition (1-4) l First cylinder (3748-4177, default 3748): Using default value 3748 Last cylinder or +size or +sizeM or +sizeK (3748-4177, default 4177): +100M Command (m for help): n Command action l logical (5 or over) p primary partition (1-4) l First cylinder (3748-4177, default 3748): Using default value 3748 Last cylinder or +size or +sizeM or +sizeK (3748-4177, default 4177): +100M Command (m for help): n Command action l logical (5 or over) p primary partition (1-4) l First cylinder (3761-4177, default 3761): Using default value 3761 Last cylinder or +size or +sizeM or +sizeK (3761-4177, default 4177): +100M Command (m for help): n Command action l logical (5 or over) p primary partition (1-4) l First cylinder (3774-4177, default 3774): Using default value 3774 Last cylinder or +size or +sizeM or +sizeK (3774-4177, default 4177): +100M Command (m for help): p Disk /dev/sda: 34.3 GB, 34359738368 bytes 255 heads, 63 sectors/track, 4177 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sda1 * 1 3315 26627706 83 Linux /dev/sda2 3316 3697 3068415 82 Linux swap / Solaris /dev/sda4 3698 4177 3855600 5 Extended /dev/sda5 3698 3722 200781 fd Linux raid autodetect /dev/sda6 3723 3747 200781 fd Linux raid autodetect /dev/sda7 3748 3760 104391 83 Linux /dev/sda8 3761 3773 104391 83 Linux /dev/sda9 3774 3786 104391 83 Linux Command (m for help): t Partition number (1-9): 7 Hex code (type L to list codes): l 0 Empty 1e Hidden W95 FAT1 80 Old Minix bf Solaris 1 FAT12 24 NEC DOS 81 Minix / old Lin c1 DRDOS/sec (FAT- 2 XENIX root 39 Plan 9 82 Linux swap / So c4 DRDOS/sec (FAT- 3 XENIX usr 3c PartitionMagic 83 Linux c6 DRDOS/sec (FAT- 4 FAT16 <32M 40 Venix 80286 84 OS/2 hidden C: c7 Syrinx 5 Extended 41 PPC PReP Boot 85 Linux extended da Non-FS data 6 FAT16 42 SFS 86 NTFS volume set db CP/M / CTOS / . 7 HPFS/NTFS 4d QNX4.x 87 NTFS volume set de Dell Utility 8 AIX 4e QNX4.x 2nd part 88 Linux plaintext df BootIt 9 AIX bootable 4f QNX4.x 3rd part 8e Linux LVM e1 DOS access a OS/2 Boot Manag 50 OnTrack DM 93 Amoeba e3 DOS R/O b W95 FAT32 51 OnTrack DM6 Aux 94 Amoeba BBT e4 SpeedStor c W95 FAT32 (LBA) 52 CP/M 9f BSD/OS eb BeOS fs e W95 FAT16 (LBA) 53 OnTrack DM6 Aux a0 IBM Thinkpad hi ee EFI GPT f W95 Ext'd (LBA) 54 OnTrackDM6 a5 FreeBSD ef EFI (FAT-12/16/ 10 OPUS 55 EZ-Drive a6 OpenBSD f0 Linux/PA-RISC b 11 Hidden FAT12 56 Golden Bow a7 NeXTSTEP f1 SpeedStor 12 Compaq diagnost 5c Priam Edisk a8 Darwin UFS f4 SpeedStor 14 Hidden FAT16 <3 61 SpeedStor a9 NetBSD f2 DOS secondary 16 Hidden FAT16 63 GNU HURD or Sys ab Darwin boot fb VMware VMFS 17 Hidden HPFS/NTF 64 Novell Netware b7 BSDI fs fc VMware VMKCORE 18 AST SmartSleep 65 Novell Netware b8 BSDI swap fd Linux raid auto 1b Hidden W95 FAT3 70 DiskSecure Mult bb Boot Wizard hid fe LANstep 1c Hidden W95 FAT3 75 PC/IX be Solaris boot ff BBT Hex code (type L to list codes): fd Changed system type of partition 7 to fd (Linux raid autodetect) Command (m for help): t Partition number (1-9): 8 Hex code (type L to list codes): fd Changed system type of partition 8 to fd (Linux raid autodetect) Command (m for help): t Partition number (1-9): 9 Hex code (type L to list codes): fd Changed system type of partition 9 to fd (Linux raid autodetect) Command (m for help): p Disk /dev/sda: 34.3 GB, 34359738368 bytes 255 heads, 63 sectors/track, 4177 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Device Boot Start End Blocks Id System /dev/sda1 * 1 3315 26627706 83 Linux /dev/sda2 3316 3697 3068415 82 Linux swap / Solaris /dev/sda4 3698 4177 3855600 5 Extended /dev/sda5 3698 3722 200781 fd Linux raid autodetect /dev/sda6 3723 3747 200781 fd Linux raid autodetect /dev/sda7 3748 3760 104391 fd Linux raid autodetect /dev/sda8 3761 3773 104391 fd Linux raid autodetect /dev/sda9 3774 3786 104391 fd Linux raid autodetect Command (m for help): w The partition table has been altered! Calling ioctl() to re-read partition table. WARNING: Re-reading the partition table failed with error 16: Device or resource busy. The kernel still uses the old table. The new table will be used at the next reboot. Syncing disks. [root@localhost ~]# partprobe /dev/sda [root@localhost ~]# mdadm --create /dev/md5 --level=5 --raid-devices=3 /dev/sda7 /dev/sda8 /dev/sda9 mdadm: array /dev/md5 started.
then we will create raid5 like this
[root@localhost ~]# mdadm –create /dev/md5 –level=5 –raid-devices=3 /dev/sda7 /dev/sda8 /dev/sda9
mdadm: array /dev/md5 started
you can also check raid5
[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sda9[2] sda8[1] sda7[0]
208640 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]
thank you
by vishnu sharma
