How To Setup ASM & ASMLIB On Native Linux Multipath Mapper disks?

(文档 ID 602952.1)

Applies to:

Oracle Database - Enterprise Edition - Version 10.1.0.2 to 12.1.0.2 [Release 10.1 to 12.1]
Linux x86
Linux x86-64
Linux Itanium
***Checked for relevance on 08-Oct-2013***

Goal

The present document provides an example about how to setup ASM & ASMLIB disks using Mapper Multipath disks.

Solution

1) Install the ASMLIB API (on each node for RAC environments) and configure it following the steps described in the next documents:

 

Oracle ASMLib

Tips on Installing and Using the Software

Configuring Oracle ASMLib on Multipath Disk

 

2) Create one partition on the mapper device located at /dev/mapper/mpath* as follow (Oracle recommends creating one partition per disk):

# kpartx -a /dev/mapper/mpath#

Where:  # is the multipathed group

Note: kpartx command creates multipathed partitions, for example partions on device mpath0 appear as /dev/mapper/mpath0p1, /dev/mapper/mpath0p2, etc., for additional information please check the next reference:

http://magazine.redhat.com/2008/07/17/tips-and-tricks-how-do-i-setup-device-mapper-multipathing-in-red-hat-enterprise-linux-4/

3) Update the kernel partition table with the new partition as follow:

 

# /sbin/partprobe

 

4) Create the ASMLIB disks on the new mapper partitions as follow:

# /etc/init.d/oracleasm createdisk  <ASMLIB disk name>  /dev/mapper/mpath<#>

Example:

# /etc/init.d/oracleasm createdisk ASMDISK1  /dev/mapper/mpath0p1

 

5) After you complete the creation of each ASMLIB disk, you will need to configure ASMLIB to use multipath disks as described in the next document (from each node on RAC environments):

Configuring Oracle ASMLib on Multipath Disk

 

You will need to update the /etc/sysconfig/oracleasm file with the next value(s) in the ORACLEASM_SCANORDER parameter:

ORACLEASM_SCANORDER="dm"

 

Or

ORACLEASM_SCANORDER="mpath dm"

 

6) If this is a RAC configuration, then on each node, execute the next commands as root user (next actions will scan the multipath disks and make them available for ASMLIB) :

# /etc/init.d/oracleasm scandisks

# /etc/init.d/oracleasm listdisks

 

7) Then connect to the ASM instance and set the ASM_DISKSTRING (disk discovery) = 'ORCL:*' as follow:

SQL> alter system set ASM_DISKSTRING = 'ORCL:*'  scope=BOTH;

 

8) Verify the ASMLIB ('ORCL:<disk name>') are discovered by ASM (from each node on RAC environments):

SQL> select path from v$asm_disk;

9) Finally, create the diskgroup(s) on the new ASMLIB disks
 
Example:

SQL> create diskgroup DATA external redundancy disk 'ORCL:DISK1';

 

Additional Resources

Community Discussions: Storage Management

Still have questions? Use the above community to search for similar discussions or start a new discussion on this subject.

NOTE:1594584.1 - White Paper: ASMLIB Installation & Configuration On MultiPath Mapper Devices (Step by Step Demo) On RAC Or Standalone Configurations.
NOTE:580153.1 - How To Setup ASM on Linux Using ASMLIB Disks, Raw Devices, Block Devices or UDEV Devices?