Red Hat GFS 5.2.1 -, Administrator'S Manual

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Chapter 3.
Installing System Software
Installing system software consists of installing a Linux kernel and the corresponding GFS software
into each node of your GFS cluster. This chapter explains how to install system software and includes
the following sections:
•
Section 3.1 Prerequisite Tasks
•
Section 3.2 Installation Tasks
•
Section 3.2.1 Installing a Linux Kernel
•
Section 3.2.2 Installing A GFS RPM
•
Section 3.2.3 Loading the GFS Kernel Modules
3.1. Prerequisite Tasks
Before installing GFS software, make sure that you have noted the key characteristics of your GFS
configuration (refer to Section 1.5 Before Configuring GFS ). Make sure that you have installed the
following software:
• Net::Telnet Perl
module
•
Clock synchronization software
• Stunnel
utility (optional)
3.1.1.
Net::Telnet Perl
Module
The
Net::Telnet Perl
module is used by several fencing agents and should be installed on all
GFS nodes. The
Net::Telnet Perl
module should be installed before installing GFS; otherwise,
GFS will not install.
You can download the
Net::Telnet Perl
module and installation instructions for the module from
the Comprehensive Perl Archive Network (CPAN) website at http://www.cpan.org.
3.1.2. Clock Synchronization Software
Make sure that each GFS node is running clock synchronization software. The system clocks in GFS
nodes need to be within a few minutes of each other for the following reasons:
•
Avoiding unnecessary inode time-stamp updates — If the node clocks are not synchronized, the
inode time stamps will be updated unnecessarily, severely impacting cluster performance. Refer to
Section 9.9 Configuring
atime
Updates for additional information.
•
Maintaining license validity — If system times are incorrect, the license may be considered invalid.