Linux System Administration

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Chapter 2: Setting Up a Linux Multifunction Server

Usage Statistics for server1.centralsoft.org

What is the filename of the rotated webserver log?

/var/log/apache/access.log.1

Synchronizing the System Clock

Computer systems’ clocks tend to drift. Therefore, a fairly basic configuration task is

to connect your system to a Network Time Protocol (NTP) server that will keep it

within a couple of seconds of the correct time.

To synchronize your system clock with an NTP server, add the following lines to /var/

spool/cron/crontabs/root:

# update time with NTP server

0 3,9,15,21 * * * /usr/sbin/rdate 128.2.136.71 | logger -t NTP

If the file doesn’t exist, you can create it with the command:

# touch /var/spool/cron/crontabs/root

The IP address 128.2.136.71 belongs to Carnegie Mellon University’s public time

server. You can use a different time server if you wish.

Modify permissions on the crontab file by running:

# chmod 600 /var/spool/cron/crontabs/root

and restart the cron service by running:

# /etc/init.d/cron restart

Installing Perl Modules Needed by SpamAssassin

Many tools depend on the Perl programming language or offer a Perl interface to let

you customize them (although other languages are gaining adherents in the open

source and Unix worlds). SpamAssassin, a critical tool for mail administrators (and

even mail users), is one program we’ll use in this book that relies on Perl. As a sys-

tem administrator, ...