This section discusses common storage practices for Oracle RAC database.
Oracle Automatic Storage Management (ASM) is the recommended volume manager which can be used for both Oracle RAC and Single Instance Oracle Databases. Oracle ASM simplifies storage management through the principle of “stripe and mirror everything” (SAME). Intelligent mirroring capabilities enable administrators to define 2- or 3-way mirrors to protect vital data. But this is not needed when using enterprise storage solutions like PowerFlex. ASM takes over the management of the disks and creates disk groups where datafile reside and are managed automatically. ASM is highly integrated with, and highly optimized for, the Oracle Database.
Some of the benefits of ASM include:
The most common way to consume PowerFlex storage is to mount as a VMFS datastore in the ESXi hypervisor. Create multiple VMFS datastores for different types of Oracle database files (datafiles, redo logfiles, archive logs, OCR files) using VMware vSphere web client. Create Shared VMDKs using multiwriter option and attach the same type of virtual drives to Oracle RAC database VMs. Oracle ASM takes control of these virtual drives like any raw devices. Thus, no extra configuration steps are required to make PowerFlex storage work with ASM.
echo noop > /sys/block/$device/queue/scheduler
echo 1024 > /sys/block/$device/queue/max_sectors_kb
KERNEL=="sd*", SUBSYSTEM=="block", PROGRAM="/lib/udev/scsi_id --page=0x83 --whitelisted --device=/dev/%k", RESULT=="36000c29f253d0fb44c9c59b18dc95a94",
SYMLINK+="oracleasm/oradata01", OWNER="grid", GROUP="asmadmin", MODE="0660"
Table 4. ASM disk group configuration
ASM disk group
Number of virtual drives
OCR and Voting file to store Grid Infrastructure related information
To store Grid Infrastructure Management repository
Database files; temporary table space; online redo logs; system-related table spaces such as SYSTEM and UNDO
Online Redo logfiles
Archives and Database backup