Use fdisk to list the physical disks available to create logical sectors on the device.Here we have external disks added with persistent storage.
[root@RACFLEX1 oracle]# fdisk -l
Disk /dev/sda: 5472 MB, 5472104448 bytes
255 heads, 63 sectors/track, 665 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x1195760c
Device Boot Start End Blocks Id System
/dev/sda1 1 665 5341581 83 Linux
Disk /dev/sdc: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x4699c8c4
Device Boot Start End Blocks Id System
/dev/sdc1 1 261 2096451 83 Linux
Disk /dev/sdb: 5472 MB, 5472104448 bytes
255 heads, 63 sectors/track, 665 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x96f39711
Device Boot Start End Blocks Id System
/dev/sdb1 1 665 5341581 83 Linux
Disk /dev/sdd: 5472 MB, 5472104448 bytes
255 heads, 63 sectors/track, 665 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/sde: 5472 MB, 5472104448 bytes
255 heads, 63 sectors/track, 665 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
Disk /dev/sdg: 55.1 GB, 55053647872 bytes
255 heads, 63 sectors/track, 6693 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00031e11
Device Boot Start End Blocks Id System
/dev/sdg1 * 1 2550 20480000 83 Linux
/dev/sdg2 2550 4463 15360000 83 Linux
/dev/sdg3 4463 4724 2097152 82 Linux swap / Solaris
/dev/sdg4 4724 6694 15824896 5 Extended
/dev/sdg5 4724 6694 15823872 83 Linux
Disk /dev/sdf: 2147 MB, 2147483648 bytes
255 heads, 63 sectors/track, 261 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000
We add primary partitions for all the devices /dev/sda , /dev/sdb, /dev/sdc, /dev/sdd …
[root@RACFLEX1 oracle]# fdisk /dev/sdd
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0x0b5c3711.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-665, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-665, default 665):
Using default value 665
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RACFLEX1 oracle]# fdisk /dev/sde
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xc148f4a1.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-665, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-665, default 665):
Using default value 665
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
[root@RACFLEX1 oracle]# fdisk /dev/sdg
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): n
No free sectors available
Command (m for help): ^Z
[1]+ Stopped fdisk /dev/sdg
[root@RACFLEX1 oracle]# ^C
[root@RACFLEX1 oracle]# fdisk /dev/sdf
Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0xa10fefb6.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
WARNING: DOS-compatible mode is deprecated. It's strongly recommended to
switch off the mode (command 'c') and change display units to
sectors (command 'u').
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 1
First cylinder (1-261, default 1):
Using default value 1
Last cylinder, +cylinders or +size{K,M,G} (1-261, default 261):
Using default value 261
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
Syncing disks.
Download oracleasmlib and oracleasmsupport rpms using yum or download from support website to use oracleasm utility !
[root@RACFLEX1 oracle]# yum install oracleasm-support
Loaded plugins: refresh-packagekit, security, ulninfo
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package oracleasm-support.x86_64 0:2.1.11-2.el6 will be installed
--> Finished Dependency Resolution
[root@RACFLEX1 oracle]# yum install kmod-oracleasm -y
Loaded plugins: refresh-packagekit, security, ulninfo
Setting up Install Process
Resolving Dependencies
--> Running transaction check
---> Package kmod-oracleasm.x86_64 0:2.0.8-16.1.el6_10 will be installed
--> Processing Dependency: kernel(__x86_indirect_thunk_rax) = 0x2ea2c95c for package: kmod-oracleasm-2.0.8-16.1.el6_10.x86_64
--> Processing Dependency: kernel >= 2.6.32-754.el6 for package: kmod-oracleasm-2.0.8-16.1.el6_10.x86_64
--> Running transaction check
---> Package kernel.x86_64 0:2.6.32-754.35.1.el6 will be installed
--> Processing Dependency: dracut-kernel >= 004-408.el6 for package: kernel-2.6.32-754.35.1.el6.x86_64
--> Running transaction check
---> Package dracut-kernel.noarch 0:004-388.0.1.el6 will be updated
---> Package dracut-kernel.noarch 0:004-411.0.9.el6 will be an update
--> Processing Dependency: dracut = 004-411.0.9.el6 for package: dracut-kernel-004-411.0.9.el6.noarch
--> Running transaction check
---> Package dracut.noarch 0:004-388.0.1.el6 will be updated
---> Package dracut.noarch 0:004-411.0.9.el6 will be an update
--> Finished Dependency Resolution
Dependencies Resolved
================================================================================
Package Arch Version Repository Size
================================================================================
Installing:
kmod-oracleasm x86_64 2.0.8-16.1.el6_10 public_ol6_latest 36 k
Installing for dependencies:
kernel x86_64 2.6.32-754.35.1.el6 public_ol6_latest 32 M
Updating for dependencies:
dracut noarch 004-411.0.9.el6 public_ol6_latest 130 k
dracut-kernel noarch 004-411.0.9.el6 public_ol6_latest 29 k
Transaction Summary
================================================================================
Install 2 Package(s)
Upgrade 2 Package(s)
Total download size: 33 M
Downloading Packages:
(1/4): dracut-004-411.0.9.el6.noarch.rpm | 130 kB 00:00
(2/4): dracut-kernel-004-411.0.9.el6.noarch.rpm | 29 kB 00:00
(3/4): kernel-2.6.32-754.35.1.el6.x86_64.rpm | 32 MB 00:50
(4/4): kmod-oracleasm-2.0.8-16.1.el6_10.x86_64.rpm | 36 kB 00:00
--------------------------------------------------------------------------------
Total 654 kB/s | 33 MB 00:51
Running rpm_check_debug
Running Transaction Test
Transaction Test Succeeded
Running Transaction
Updating : dracut-004-411.0.9.el6.noarch 1/6
Updating : dracut-kernel-004-411.0.9.el6.noarch 2/6
Installing : kernel-2.6.32-754.35.1.el6.x86_64 3/6
Installing : kmod-oracleasm-2.0.8-16.1.el6_10.x86_64 4/6
Cleanup : dracut-kernel-004-388.0.1.el6.noarch 5/6
Cleanup : dracut-004-388.0.1.el6.noarch 6/6
Verifying : kernel-2.6.32-754.35.1.el6.x86_64 1/6
Verifying : dracut-004-411.0.9.el6.noarch 2/6
Verifying : dracut-kernel-004-411.0.9.el6.noarch 3/6
Verifying : kmod-oracleasm-2.0.8-16.1.el6_10.x86_64 4/6
Verifying : dracut-kernel-004-388.0.1.el6.noarch 5/6
Verifying : dracut-004-388.0.1.el6.noarch 6/6
Installed:
kmod-oracleasm.x86_64 0:2.0.8-16.1.el6_10
Dependency Installed:
kernel.x86_64 0:2.6.32-754.35.1.el6
Dependency Updated:
dracut.noarch 0:004-411.0.9.el6 dracut-kernel.noarch 0:004-411.0.9.el6
Complete!
[root@RACFLEX1 oracle]# rpm -qa|grep oracleasm
oracleasm-support-2.1.11-2.el7.x86_64
oracleasmlib-2.0.12-1.el7.x86_64
First configure oracleasm
[root@RACFLEX1 oracle]# oracleasm configure -i
Configuring the Oracle ASM library driver.
This will configure the on-boot properties of the Oracle ASM library
driver. The following questions will determine whether the driver is
loaded on boot and what permissions it will have. The current values
will be shown in brackets ('[]'). Hitting <ENTER> without typing an
answer will keep that current value. Ctrl-C will abort.
Default user to own the driver interface []: oracle
Default group to own the driver interface []: oinstall
Start Oracle ASM library driver on boot (y/n) [n]: y
Scan for Oracle ASM disks on boot (y/n) [y]: y
Writing Oracle ASM library driver configuration: done
Then initialize oracleasm
[root@RACFLEX1 oracle]# oracleasm init
Creating /dev/oracleasm mount point: /dev/oracleasm
Loading module "oracleasm": oracleasm
Configuring "oracleasm" to use device physical block size
Mounting ASMlib driver filesystem: /dev/oracleasm
Create the logical disks on top of partitions for the ASM diskgroups
[root@RACFLEX1 oracle]# oracleasm createdisk DATA1 /dev/sdd1
Writing disk header: done
Instantiating disk: done
[root@RACFLEX1 oracle]# oracleasm createdisk FRA1 /dev/sde1
Writing disk header: done
Instantiating disk: done
[root@RACFLEX1 oracle]# oracleasm createdisk CRS1 /dev/sdf1
Writing disk header: done
Instantiating disk: done
Scan to verify stale or corrupted disks and list each ASM disks
[root@RACFLEX1 oracle]# oracleasm scandisks
Reloading disk partitions: done
Cleaning any stale ASM disks...
Scanning system for ASM disks...
[root@RACFLEX1 oracle]# oracleasm listdisks
CRS
CRS1
DATA
DATA1
FRA
FRA1
[root@RACFLEX1 oracle]#
while installing a database ,we can specify these disks to create ASM diskgroups
