Linux Server Security, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

Using Swatch for Automated Log Monitoring

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Again, if you want Swatch to monitor multiple files, you’ll need to run Swatch multi-

ple times, with at least a different tailing target (

-t value) specified each time and

probably a different configuration file for each as well.

Further startup options are described in the swatch(1) manpage.

Fine-Tuning Swatch

Once Swatch is configured and running, we must turn our attention to the Gold-

ilocks Goal: we want Swatch to be running neither “too hot” (alerting us about rou-

tine or trivial events) nor “too cold” (never alerting us about anything). But what

constitutes “just right”? There are as many answers to this question as there are uses

for Unix.

Anyhow, you don’t need me to tell you what constitutes nuisance-level reporting: if

it happens, you’ll know it. You may even experience a scare or two in responding to

events that set off alarms but turn out to be harmless nonetheless. Read the manual,

tweak .swatchrc, and stay the course.

The other scenario, in which too little is watched for, is much harder to address,

especially for the beginning system administrator. By definition, anomalous events

don’t happen very frequently, so how do you anticipate how they’ll manifest them-

selves in the logs? My first bit of advice is to get in the habit ...