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This module is contained in the mod_log_config.c file,
and is compiled in by default in Apache 1.2. mod_log_config replaces
mod_log_common in Apache 1.2. Prior to version 1.2, mod_log_config was
an optional module. It provides for logging of the requests made to
the server, using the Common Log Format or a user-specified format.
Three directives are provided by this module: TransferLog
to create a log file, LogFormat to set a custom format,
and CustomLog to define a log file and format in one go.
The TransferLog and CustomLog directives can
be used multiple times in each server to cause each request to be
logged to multiple files.
CookieLog directive,
used to log user-tracking information created by mod_usertrack. The use of
CookieLog is deprecated, and a CustomLog
should be defined to log user-tracking information instead.
RefererIgnore functionality from
mod_log_referer. The effect
of RefererIgnore can be achieved by combinations of
SetEnvIf directives
and conditional CustomLog definitions.
LogFormat and CustomLog.
host ident authuser date request status bytesIf a token does not have a value then it is represented by a hyphen (-). The meanings and values of these tokens are as follows:
date = [day/month/year:hour:minute:second zone]
day = 2*digit
month = 3*letter
year = 4*digit
hour = 2*digit
minute = 2*digit
second = 2*digit
zone = (`+' | `-') 4*digit").
LogFormat and
CustomLog is a string. This string is logged to the log
file for each request. It can contain literal characters copied into
the log files, and `%' directives which are replaced in the log file
by the values as follows:
%...b: Bytes sent, excluding HTTP headers.
%...f: Filename
%...{FOOBAR}e: The contents of the environment variable FOOBAR
%...h: Remote host
%...a: Remote IP-address
%...{Foobar}i: The contents of Foobar: header line(s) in the request
sent to the server.
%...l: Remote logname (from identd, if supplied)
%...{Foobar}n: The contents of note "Foobar" from another module.
%...{Foobar}o: The contents of Foobar: header line(s) in the reply.
%...p: The canonical Port of the server serving the request
%...P: The process ID of the child that serviced the request.
%...r: First line of request
%...s: Status. For requests that got internally redirected, this
is status of the *original* request --- %...>s for the last.
%...t: Time, in common log format time format
%...{format}t: The time, in the form given by format, which should
be in strftime(3) format.
%...T: The time taken to serve the request, in seconds.
%...u: Remote user (from auth; may be bogus if return status (%s) is 401)
%...U: The URL path requested.
%...v: The canonical ServerName of the server serving the request.
%...V: The server name according to the UseCanonicalName setting.
The `...' can be nothing at all (e.g., "%h %u %r %s %b"), or it can
indicate conditions for inclusion of the item (which will cause it
to be replaced with `-' if the condition is not met). Note that
there is no escaping performed on the strings from %r, %...i and
%...o; some with long memories may remember that I thought this was
a bad idea, once upon a time, and I'm still not comfortable with
it, but it is difficult to see how to `do the right thing' with all
of `%..i', unless we URL-escape everything and break with CLF.
The forms of condition are a list of HTTP status codes, which may or may not be preceded by `!'. Thus, `%400,501{User-agent}i' logs User-agent: on 400 errors and 501 errors (Bad Request, Not Implemented) only; `%!200,304,302{Referer}i' logs Referer: on all requests which did not return some sort of normal status.
Note that the common log format is defined by the string "%h %l
%u %t \"%r\" %s %b", which can be used as the basis for
extending for format if desired (e.g., to add extra fields at the end).
NCSA's extended/combined log format would be "%h %l %u %t \"%r\" %s %b \"%{Referer}i\" \"%{User-agent}i\"".
Note that the canonical ServerName
and Port of the server serving the request
are used for %v and %p respectively. This
happens regardless of the
UseCanonicalName setting because
otherwise log analysis programs would have to duplicate the entire
vhost matching algorithm in order to decide what host really served
the request.
TransferLog and CustomLog directives can
be given more than once to log requests to multiple log files. Each
request will be logged to all the log files defined by either of these
directives.
The CookieLog directive sets the filename for logging of cookies. The filename is relative to the ServerRoot. This directive is included only for compatibility with mod_cookies, and is deprecated.
The first argument is the filename to which log records should be written. This is used exactly like the argument to TransferLog; that is, it is either a full path or relative to the current server root.
The format argument specifies a format for each line of the log file. The options available for the format are exactly the same as for the argument of the LogFormat directive. If the format includes any spaces (which it will do in almost all cases) it should be enclosed in double quotes.
Instead of an actual format string, you can use a format nickname defined with the LogFormat directive.
The behaviour of this form of the CustomLog directive is almost
identical to the standard CustomLog
directive. The difference is that the 'env=' clause controls
whether a particular request will be logged in the specified file or
not. If the specified environment variable is set for the
request (or is not set, in the case of a 'env=!name'
clause), then the request will be logged.
Environment variables can be set on a per-request basis using the mod_setenvif and/or mod_rewrite modules. For example, if you don't want to record requests for all GIF images on your server in a separate logfile but not your main log, you can use:
SetEnvIf Request_URI \.gif$ gif-image
CustomLog gif-requests.log common env=gif-image
CustomLog nongif-requests.log common env=!gif-image
LogFormat "%h %l %u %t \"%r\"
%s %b"This sets the format of the default logfile named by the TransferLog directive . See the section on Custom Log Formats for details on the format arguments.
If you include a nickname for the format on the directive line, you can use it in other LogFormat and CustomLog directives rather than repeating the entire format string.
A LogFormat directive which defines a nickname does nothing else -- that is, it only defines the nickname, it doesn't actually apply the format and make it the default.
The TransferLog directive adds a log file in the format defined by the most recent LogFormat directive, or Common Log Format if no other default format has been specified. File-pipe is one of
