File System for Shared Application (shared APPL_TOP)

Most of the Oracle Application DBA's has challenge for OS file system requirement for Shared Application Binaries (shared APPL_TOP).

For shared application binaries requirement is cluster file systems. Some of the options are available NFS file system, OCFS/OCFS2, Symentic cluster file systems.

NFS file system is not a high availability solutions for shared application binaries, if orignal node fails file system is not available on secondary node.

Symentic file is not available in small scale companies and have additional cost and administrations.

OCFS or OCFS2 is not supported by Oracle for shared APPL_TOP (Shared Application) due to performance issue and behaviour/purpose of these file ssytems.

One best choice is available as GFS file system Linux 5 and onwards. GFS can be installed in Linux 4 also but that is not the recommened. There are several methods available in GFS file system for fencing the node like APAC, Brocade Switches. Brocade Switches are best options for node fencing as this is will be available in all companies. performance, reliable,FREE available, can be installed with few OS packages , easy to configure some of the key features for GFS file system.

make sure you create seprate LUN on SAN and assign it to all the application nodes.

Follwoing packages are required on Linux to configure the GFS (Global File system)

gfs-utils
kmod-gfs-PAE-
system-config-cluster
rgmanager


make sure SELinux and iptables are disabled.

and following files need to configured..
cluster.conf
fence.css
nodes.css

use "system-config-cluster" utility to create the GFS cluster file system.

use "gfs_mkfs" command to create the cluster file system.