Logs and Monitoring for Apache Servers | Page 3
Logs and Monitoring for Apache Servers
Monitoring Apache with SNMP
There are a couple of open-source modules that add Simple Network Management Protocol (SNMP) capabilities to the Apache web server. This protocol is commonly used to manage network servers and equipment from a central console such as HP OpenView and Tivoli. With this module, you can easily monitor Apache performance in real time, including server uptime, load average, number of errors in a certain period of time, number of bytes and requests served, and many other metrics. The SNMP modules can also generate alarms when a certain threshold or error condition is met, such as a sudden increase in the number of simultaneous client connections.
For Apache 1.3, you can use
mod_snmp, which can be found at http://www.mod-snmp.com/ and supports SNMP version 1 and 2. It requires patching of the Apache core.
For Apache 2, you can use a similar module called
mod_apache_snmp. It can be found at http://modapachesnmp.sourceforge.net/. This module supports versions 1, 2, and 3 of the SNMP protocol and can be compiled as a DSO, without the need to patch Apache.
Analyzing Your Logs with Open-source Tools
There are a number of commercial and open-source tools that you can use to process and display your log data. They usually take a log file, analyze its contents, and create a series of web pages with the relevant statistics.
The following are some popular, freely available, open source applications for general log analysis:
Monitoring Your Logs in Real Time
In addition to
mod_status and the various SNMP modules described earlier, you can use the
apachetop command-line tool, which can be downloaded from http://clueful.shagged.org/apachetop/.
This tool works similarly to the Unix
top command-line tool, but instead of displaying the status of the operating system, it displays the status of the web server in real time.
If you run Apache on a Unix system and you have a website with low traffic, you can use the
tail command-line utility to rudimentarily monitor, in real time, log entries both to your access and error logs:
There are additional programs that enable you to quickly identify problems by scanning your error log files for specific errors, malformed requests, and so on, and reporting on them:
- Logscan can be found at http://www.garand.net/security.php
- ScanErrLog can be found at http://www.librelogiciel.com/software/
Logging Requests to a DatabaseApache itself does not include tools for logging to databases, but a few third-party scripts and modules are available: