iTP Secure WebServer System Administrator's Guide (iTPWebSvr 5.1+)

Configuring the iTP Secure WebServer
iTP Secure WebServer System Administrator’s Guide—522659-001
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Planning Space for Logs
Common Log Format (CLF)
The common log format (CLF) is used by the access and error log files and is specified
by the AccessLog and ErrorLog configuration directives (see Appendix A,
Configuration Directives). This format is supported by other web servers and by many
log-analysis tools. If you already are using or have such tools, you may wish to use CLF.
Note that the WebReporter is most effective if you use the extended log format
described below. For more information about the WebReporter, refer to the iTP Secure
WebServer WebReporter Command Reference Manual and the iTP Secure WebServer
WebReporter User’s Guide.
Extended Log Format (ELF)
The extended log format (ELF) is used by the extended log file and is specified by the
ExtendedLog configuration directive (see ExtendedLog on page A-18). ELF implements
several features not available with CLF including:
•
All error and access information for a particular request is recorded in a single log
entry. This integration of information eliminates the need to correlate entries in the
error log with separate entries in the access log.
•
Fields are provided for the web-browser software type, the referrer, and the request
begin and end times.
•
Fields are provided for security information, such as the name of an authenticated
user.
•
The name/value pairs used for the information fields support the addition of new
logging fields (such as a field for security information).
•
The overall format makes it easy to write new log-analysis programs.
If you plan to write your own log-analysis programs, or if you need to use the additional
information fields, you may wish to specify ELF. ELF also allows you to make best use
of WebReporter. For more information, refer to the iTP Secure WebServer WebReporter
Command Reference Manual and the iTP Secure WebServer WebReporter User’s Guide.
CLF and ELF are described in detail in Appendix C, Server Log File Formats
.
Planning Space for Logs
Because the server log files can grow quickly in size, you should plan adequate space
for them.
Table 7-1
shows the expected daily growth in the size of the server log files for various
aggregate numbers of daily requests. This table assumes a typical entry size of 100 bytes
for the access log file and a typical entry size of 150 bytes for the extended log file. The
size of the error log file will depend on the frequency of access errors. Table 7-1
assumes that the error log file will grow at 20 percent the rate of the access log file.