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Quản trị hệ thống linux nâng cao
For more information on logrotate, see the logrotate(8) man page, which contains a
description of the program and the syntax of the configuration file.
5.4.5
Chủ đề nâng cao - klogd
Before moving away from syslog, I’d like to note a couple of advanced topics for ambitious
readers. These tips may save you some grief when trying to understand syslog-related topics.
First, the syslog daemon is actually part of the sysklogd package, which contains a
second daemon called klogd. It’s klogd’s job to receive information and error messages
from the kernel, and pass them on to syslogd for categorization and logging. The messages
received by klogd are exactly the same as those you can retrieve using the dmesg command.
The difference is that dmesg prints the current contents of a ring buffer in the kernel,
whereas klogd is passing the messages to syslogd so that they won’t be lost when the ring
wraps around.
5.4.6
Chủ đề nâng cao - các chương trình ghi nhật ký khác
Second, there are alternatives to the standard sysklogd package. The alternatives attempt to
be more efficient, easier to configure, and possibly more featureful than sysklogd. Syslog-ng
and Metalog seem to be some of the more popular alternatives; you might investigate them
if you find sysklogd doesn’t provide the level of power you need.
Third, you can log messages in your scripts using the logger command. See the logger(1)
man page for more information.
5.5
Tóm lược
Congratulations, you’ve reached the end of this tutorial! Well, almost. There were a couple
of topics that we were unable to include in our first four tutorials due to space limitations.
Fortunately, we have a couple of good resources that will help you get up to speed on these
topics in no time. Be sure to cover these particular tutorials if you are planning to get your
LPIC level 1 certification.
We didn’t have quite enough room to cover the important topic of system backups in
this tutorial. Fortunately, IBM developerWorks already has a tutorial on this subject, called
Backing up your Linux machines. In this tutorial, you’ll learn how to back up Linux systems
using a tar variant called star. You’ll also learn how to use the mt command to control tape
functions.
The second topic that we weren’t quite able to fit in was periodic scheduling. Fortu-
nately, there’s some good cron documentation available at Indiana University. cron is used
to schedule jobs to be executed at a specific time, and is an important tool for any system
administrator.
On the next page, you’ll find a number of resources that you will find helpful in learning
more about the subjects presented in this tutorial.
