Oracle ASM (Automated Storage Management) is a data volume manager for Oracle databases. ASMLib is an optional utility that can be used on Linux systems to manage Oracle ASM devices. ASM assists users in disk management by keeping track of storage devices dedicated to Oracle databases and allocating space on those devices according to the requests from Oracle database instances.
ASMLib consists of the following components:
- An open source (GPL) kernel module package: kmod-oracleasm
- An open source (GPL) utilities package: oracleasm-support
- A closed source (proprietary) library package: oracleasmlib
ASM features and functionality are available without ASMLib. The use of ASMLib does not affect database performance.
Installing ASMLib:
1. Install the ASMLib kernel module package as root using the following command:
# yum install kmod-oracleasm
2. Download the ASMLib utilities package (oracleasm-support) and ASMLib library package (oracleasmlib) from the following location:
http://www.oracle.com/technetwork/server-storage/linux/asmlib/rhel6-1940776.html
3. Install the ASMLib library package obtained from step 2 as root using the following command, with the downloaded package:
# yum localinstall oracleasmlib-[version].x86_64.rpm # Where [version] is the revision downloaded in the previous step
4. Install the ASMLib utilities package obtained from step 2 as root using the following command, with the downloaded package:
# yum localinstall oracleasm-support-[version].x86_64.rpm
All three required ASMLib components should now be installed on your system.
Configuring ASMLib
1. Configure ASMLib using the following command. The script will ask for a user and group that will own the ASM driver access point. In our case, we will use the database user “oracle” and group “oinstall”. But you can also have different user and group than these.
# /etc/init.d/oracleasm configure
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 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
Fix permissions of Oracle ASM disks on boot (y/n) [y]: y
Writing Oracle ASM library driver configuration [ OK ]
Creating /dev/oracleasm mount point [ OK ]
Loading module "oracleasm" [ OK ]
Mounting ASMlib driver filesystem [ OK ]
Scanning system for ASM disks [ OK ]
This loads the oracleasm.o driver and mounts the ASM driver filesystem. In case of any failure you can check the log file /var/log/oracleasm.
To enable or disable automatic start of ASMLib driver
To disable automatic start of ASMLib on reboot of system :
# /etc/init.d/oracleasm disable Writing Oracle ASM library driver configuration [ OK ] Unmounting ASMlib driver filesystem [ OK ] Unloading module "oracleasm" [ OK ]
To enable automatic start of ASMLib on reboot of system :
# /etc/init.d/oracleasm enable Writing Oracle ASM library driver configuration [ OK ] Loading module "oracleasm" [ OK ] Mounting ASMlib driver filesystem [ OK ] Scanning system for ASM disks [ OK ]