Creation of Partition in RHEL 6/Linux

Partitions are created on a single hard disk with required file system management like the local drives created in windows operating system.

Partitions are divided into three types:

1.      Primary Partition

2.      Extended Partition

3.      Logical partition

Primary partitions are limited to four partitions, extended partition can be created only once and Logical has an advantage as we can create eleven logical partitions.

Primary Partition

 To get experienced with primary partition in your hard disk follow the below procedure:

STEP 1: Create Primary Partition

STEP 2: Verify Partition Created

STEP 3: Apply File System

STEP 4: Create Mount Point

STEP 5: Make Permanent Mounting

STEP 1: To create a partition type the fdisk command as shown below and follow the guidelines.

root@demo ~]# fdisk -cu /dev/vda

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): n Command action    e   extended    p   primary partition (1-4) p Partition number (1-4): 3 First sector (9914368-12582911, default 9914368): (leave empty) Using default value 9914368 Last sector, +sectors or +size{K,M,G} (9914368-12582911, default 12582911): +200M Command (m for help): p Disk /dev/vda: 6442 MB, 6442450944 bytes 16 heads, 63 sectors/track, 12483 cylinders, total 12582912 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00076b5c    Device Boot      Start         End      Blocks   Id  System /dev/vda1   *        2048      526335      262144   83  Linux /dev/vda2          526336     9914367     4694016   8e  Linux LVM /dev/vda3         9914368    10323967      204800   83  Linux 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 or after you run partprobe(8) or kpartx(8) Syncing disks.

STEP 2: Check the partition is created and enter the “partx” command twice. Don’t be worried about the error; it’s a bug in RHEL linux 6

[root@demo ~]#  partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

[root@demo ~]#  partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

BLKPG: Device or resource busy

error adding partition 3

STEP 3: Format the partition as per your requirement for the file system. Here I have taken ext4 file system.

[root@demo ~]# mkfs.ext4 /dev/vda3

mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=1024 (log=0) Fragment size=1024 (log=0) Stride=0 blocks, Stripe width=0 blocks 51200 inodes, 204800 blocks 10240 blocks (5.00%) reserved for the super user First data block=1 Maximum filesystem blocks=67371008 25 block groups 8192 blocks per group, 8192 fragments per group 2048 inodes per group Superblock backups stored on blocks:             8193, 24577, 40961, 57345, 73729 Writing inode tables: done                            Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 34 mounts or 180 days, whichever comes first.  Use tune2fs -c or -i to override.

STEP 4: Create a mount point .i.e. create a directory where you store file and folders then assign the directory as a mount point of the partition.

[root@demo ~]# mkdir /storage

[root@demo ~]# Mount the device.

[root@demo ~]# mount <device> <mountpoint>

[root@demo ~]# mount /dev/vda3 /storage

[root@demo ~]# df –h

Filesystem Size  Used Avail Use% Mounted on /dev/mapper/vgsrv-root                       3.3G  2.4G  758M  77% / tmpfs                 499M  100K  499M   1% /dev/shm /dev/vda1             248M   33M  203M  14% /boot /dev/mapper/vgsrv-home                       248M   11M  226M   5% /home /dev/vda3             194M  5.6M  179M   4% /storage

STEP 5: If you want to make permanent mounting then add device name and its details into /etc/fstab file. It is helpful in case of  system crash for any .

[root@demo ~]# vim /etc/fstab

After addition of device details into the file check if there are any errors

[root@demo ~]# mount -a

[root@demo ~]# df –hT

Filesystem    Type    Size  Used Avail Use% Mounted on /dev/mapper/vgsrv-root               ext4    3.3G  2.4G  757M  77% / tmpfs        tmpfs    499M  264K  499M   1% /dev/shm /dev/vda1     ext4    248M   33M  203M  14% /boot /dev/mapper/vgsrv-home               ext4    248M   11M  226M   5% /home /dev/vda3     ext4    194M  5.6M  179M   4% /storage

Extended Partition

STEP 1: Create Primary Partition

STEP 2: Verify Partition Created

STEP 1: To create a partition type the fdisk command as shown below and follow the guidelines.

# fdisk -cu /dev/vda

Command (m for help): n Command action    e   extended    p   primary partition (1-4) e Selected partition 4 First sector (10323968-12582911, default 10323968): (leave empty) Using default value 10323968 Last sector, +sectors or +size{K,M,G} (10323968-12582911, default 12582911): (leave empty) Using default value 12582911 Command (m for help): p Disk /dev/vda: 6442 MB, 6442450944 bytes 16 heads, 63 sectors/track, 12483 cylinders, total 12582912 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00076b5c    Device Boot      Start         End      Blocks   Id  System /dev/vda1   *        2048      526335      262144   83  Linux /dev/vda2          526336     9914367     4694016   8e  Linux LVM /dev/vda3         9914368    10323967      204800   83  Linux /dev/vda4        10323968    12582911     1129472    5  Extended 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 or after you run partprobe(8) or kpartx(8) Syncing disks.

STEP 2: Check the partition is created and enter the “partx” command twice. Don’t be worried about the error; it’s a bug in RHEL linux 6

[root@demo ~]# partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

BLKPG: Device or resource busy

error adding partition 3

[root@demo ~]# partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

BLKPG: Device or resource busy

error adding partition 3

BLKPG: Device or resource busy

error adding partition 4

Logical partition

To create the logical partition, follow the procedure given below:

STEP 1: Create Primary Partition

STEP 2: Verify Partition Created

STEP 3: Apply File System

STEP 4: Create Mount Point

STEP 5: Make Permanent Mounting

STEP 1: To create a partition type the fdisk command as shown below and follow the guidelines.

[root@demo ~]# fdisk -cu /dev/vda

Command (m for help): n First sector (10326016-12582911, default 10326016): (leave empty) Using default value 10326016 Last sector, +sectors or +size{K,M,G} (10326016-12582911, default 12582911): +120M Command (m for help): p Disk /dev/vda: 6442 MB, 6442450944 bytes 16 heads, 63 sectors/track, 12483 cylinders, total 12582912 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00076b5c    Device Boot      Start         End      Blocks   Id  System /dev/vda1   *        2048      526335      262144   83  Linux /dev/vda2          526336     9914367     4694016   8e  Linux LVM /dev/vda3         9914368    10323967      204800   83  Linux /dev/vda4        10323968    12582911     1129472    5  Extended /dev/vda5        10326016    10571775      122880   83  Linux 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 or after you run partprobe(8) or kpartx(8) Syncing disks.

STEP 2: Check the partition is created and enter the “partx” command twice. Don’t be worried about the error; it’s a bug in RHEL linux 6

[root@demo ~]# partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

BLKPG: Device or resource busy

error adding partition 3

BLKPG: Device or resource busy

error adding partition 4

BLKPG: Device or resource busy

error adding partition 5

[root@demo ~]# partx -a /dev/vda

BLKPG: Device or resource busy

error adding partition 1

BLKPG: Device or resource busy

error adding partition 2

BLKPG: Device or resource busy

error adding partition 3

BLKPG: Device or resource busy

error adding partition 4

BLKPG: Device or resource busy

error adding partition 5

STEP 3: Format the partition as per your requirement for the file system. Here I have taken ext4 file system.

[root@demo ~]# mkfs.ext4 /dev/vda5

mke2fs 1.41.12 (17-May-2010) Could not stat /dev/vda5 --- No such file or directory The device apparently does not exist; did you specify it correctly? If the above error appears, then reboot the system. [root@demo ~]# init 6 [root@demo ~]# partx -a /dev/vda BLKPG: Device or resource busy error adding partition 1 BLKPG: Device or resource busy error adding partition 2 BLKPG: Device or resource busy error adding partition 3 BLKPG: Device or resource busy error adding partition 4 BLKPG: Device or resource busy error adding partition 5 [root@demo ~]# partx -a /dev/vda BLKPG: Device or resource busy error adding partition 1 BLKPG: Device or resource busy error adding partition 2 BLKPG: Device or resource busy error adding partition 3 BLKPG: Device or resource busy error adding partition 4 BLKPG: Device or resource busy error adding partition 5 [root@demo ~]# mkfs.ext4 /dev/vda5 mke2fs 1.41.12 (17-May-2010) Filesystem label= OS type: Linux Block size=1024 (log=0) Fragment size=1024 (log=0) Stride=0 blocks, Stripe width=0 blocks 30720 inodes, 122880 blocks 6144 blocks (5.00%) reserved for the super user First data block=1 Maximum filesystem blocks=67371008 15 block groups 8192 blocks per group, 8192 fragments per group 2048 inodes per group Superblock backups stored on blocks:             8193, 24577, 40961, 57345, 73729 Writing inode tables: done                            Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 24 mounts or 180 days, whichever comes first.  Use tune2fs -c or -i to override.

STEP 4: Create a mount point .i.e. create a directory where you store file and folders then assign the directory as a mount point of the partition.

[root@demo ~]# mkdir /mystorage

[root@demo ~]# mount /dev/vda5 /mystorage/

[root@demo ~]# df –hT

Filesystem    Type    Size  Used Avail Use% Mounted on /dev/mapper/vgsrv-root               ext4    3.3G  2.4G  759M  77% / tmpfs        tmpfs    499M  100K  499M   1% /dev/shm /dev/vda1     ext4    248M   33M  203M  14% /boot /dev/mapper/vgsrv-home               ext4    248M   11M  226M   5% /home /dev/vda3     ext4    194M  5.6M  179M   4% /storage /dev/vda5     ext4    117M  5.6M  105M   6% /mystorage

STEP 5: If you want to make permanent mounting then add device name and its details into /etc/fstab file.

[root@demo ~]# vim /etc/fstab

[root@demo ~]# mount -a

After addition of device details into the file check if there are any errors

[root@demo ~]# mount -a

[root@demo ~]# df –hT

Filesystem    Type    Size  Used Avail Use% Mounted on /dev/mapper/vgsrv-root               ext4    3.3G  2.4G  759M  77% / tmpfs        tmpfs    499M  260K  499M   1% /dev/shm /dev/vda1     ext4    248M   33M  203M  14% /boot /dev/mapper/vgsrv-home               ext4    248M   11M  226M   5% /home /dev/vda3     ext4    194M  5.6M  179M   4% /storage /dev/vda5     ext4    117M  5.6M  105M   6% /mystorage