Here is a short note, if you are looking for packages (RPM) for Oracle ASMLib (oracleasm) for RedHat Linux or other Linux distributions. There are three components of ASMLib. kernel driver (oracleasm-kmod) userspace tools (oracleasm-support) userspace libary (oracleasmlib) CentOS/RHEL/OEL To find the OS version of the RHEL/CentOS servers, use the below command: # cat /etc/redhat-release Oracle provide ASMLib driver & Library & Tools for: 1. Oracle ASMLib Downloads for Red Hat … [Read more...] about Where to find ASMLib / oracleasm RPMs for CentOS/RHEL, SUSE, OEL
ASM
New Background Processes In Oracle Database 12c
The post provides information on new background processes introduced in 12c. Background ProcessDescription BWnnDatabase Writer Processes FENCFence Monitor Process IPC0IPC Service Background Process LDDnGlobal Enqueue Service Daemon Helper Slave LGnnLog Writer Worker LREGListener Registration Process OFSDOracle File Server Background Process RPOPInstant Recovery Repopulation Daemon SAnnSGA Allocator SCRBASM Disk Scrubbing Master Process SCRnASM Disk Scrubbing Slave … [Read more...] about New Background Processes In Oracle Database 12c
Oracle Automatic Storage Management (ASM) concepts
The post provides a quick overview of Oracle Automatic Storage Management (ASM) concepts and operations. ASM Basics - ASM exists to manage file storage for the RDBMS. - ASM does NOT perform I/O on behalf of the RDBMS. I/O is performed by the RDBMS processes as it does with other storage types. Thus, ASM is not an intermediary for I/O (would be a bottleneck). - I/O can occur synchronously or asynchronously depending on the value of the DISK_ASYNCH_IO parameter. - Disks are RAW devices to … [Read more...] about Oracle Automatic Storage Management (ASM) concepts
ASM background processes in 11gR2
Here is a short note on ASM background processes and their purpose in managing Oracle ASM instances. Background ProcessDescription ASMBASM Background Process RBALASM Rebalance Master Process ARBnASM Rebalance Process DBWRDatabase Writer Process SMONSystem Monitor Process CKPTCheckpoint Process PSP0Process Spawner Process GMONASM Disk Group Monitor Process MARKMark AU for Resynchronization Coordinator Process VKTMVirtual Keeper of Time Process LGWRLog Writer Process … [Read more...] about ASM background processes in 11gR2
CentOS / RHEL 7 : How to set udev rules for ASM on multipath disks
Udev is the mechanism used to create and name /dev device nodes corresponding to the devices that are present in the system. Udev uses matching information provided by sysfs with rules provided by the user to dynamically add the required device nodes. The post describes how to set udev rules for ASM disks in a dm multipath environment. The multipath disk used as an example is /dev/mapper/multipathx. We will be setting the udev rule for the multipath disks to have ownership of … [Read more...] about CentOS / RHEL 7 : How to set udev rules for ASM on multipath disks
How to Configure Device File owner/group with udev rules
What is udev and udev rules Udev is the mechanism used to create and name /dev device nodes corresponding to the devices that are present in the system. Udev uses matching information provided by sysfs with rules provided by the user to dynamically add the required device nodes. There are no static files under /dev directory for devices, devices are created/removed dynamically by udev(or udevd) which is a daemon monitoring what devices are connected/disconnected on to the kernel, and run … [Read more...] about How to Configure Device File owner/group with udev rules
How to install and configure Oracle ASMLIB on Native Linux multipath mapper devices
The post describes the process about how to setup ASM & ASMLIB disks using Mapper Multipath disks. The process involves : Installing and configuring the ASMLIB software Creating partitions on multipath devices using kpartx Creating ASM disks on new partitions updating the configuration file /etc/sysconfig/oracleasm Creating ASM disk groups 1. Install and configure ASMLIB software Install the ASMLIB (on each node for RAC environments) and configure it. ASMLib consists of the … [Read more...] about How to install and configure Oracle ASMLIB on Native Linux multipath mapper devices
How to trace asmcmd command on UNIX/Linux
Question : The asmcmd command execution is slow. How to trace the asmcmd command? Answer: You are seeing some errors or slow performance issue with command execution on asmcmd. And you wish to get more information on the command execution. The exception raised from asmcmd is not very descriptive and more of generic errors are reported for different issues. Below are some of the ways in which you can trace the asmcmd command to troubleshoot the performance issues with the execution of the … [Read more...] about How to trace asmcmd command on UNIX/Linux
CentOS / RHEL : Installing and Configuring ASMLib
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 … [Read more...] about CentOS / RHEL : Installing and Configuring ASMLib
How to Move a Datafile from Filesystem to ASM Using ASMCMD CP Command
Question : A datafile was wrongly added on file system instead of ASM diskgroup. How to move it to the ASM disk group again? Answer : 1) Make sure the datafile to be moved is OFFLINE before proceeding : SQL> alter system switch logfile; System altered. SQL> select file_name, file_id from dba_data_files; FILE_NAME FILE_ID --------------------- /u01/oracle/oradata/test1.dbf 6 SQL> alter database datafile 6 offline; Database altered. SQL> select file_name, file_id, online_status from … [Read more...] about How to Move a Datafile from Filesystem to ASM Using ASMCMD CP Command