Red Hat LINUX 7.2 Reference Manual page 205

Section 13.3:Configuration Directives in httpd.conf
The error log is a good place to look if your Web server generates any errors or fails, and you are not
sure what happened.
13.3.45 LogLevel
LogLevel sets how verbose the error messages in the error logs will be. LogLevel can be set (from
least verbose to most verbose) to emerg, alert, crit, error, warn, notice, info or debug.
Your Web server's LogLevel is set to warn.
13.3.46 LogFormat
The LogFormat directives in your httpd.conf file set up a format for the messages in your access
log. The actual LogFormat used will depend on the settings given in the CustomLog directive (see
Section 13.3.47, CustomLog ).
13.3.47 CustomLog
CustomLog identifies the log file and the log file format. In your Web server's default con-
figuration, CustomLog defines the log file in which accesses to your Web server are recorded:
/var/log/httpd/access_log. You will need to know the location of this file if you want to
generate any access-based server performance statistics for your Web server.
CustomLog also sets the log file format to combined. The common logfile format looks like this:
remotehost rfc931 authuser [date] "request" status bytes referer user-agent
remotehost
The remote hostname. If the hostname is not available from DNS, or if HostnameLookups
is set to Off, then remotehost will be the IP address of the remote host.
rfc931
Not used. You will see a - in the log file in its place.
authuser
If authentication was required, this is the username with which the user identified him or herself.
Usually, this is not used, so you will see a - in its place.
[date]
The date and time of the request.
"request"
The request string exactly as it came from the browser or client.
status
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