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      This module provides for forensic logging of the requests made to the server
Status: Extension
     Source File:
    mod_log_forensic.c
     Module Identifier:
    log_forensic_module
     Compatibility: Available in
    Version 1.3.30 and later.
This module provides for forensic logging of client requests. Logging is done before and after processing a request, so the forensic log contains two log lines for each request. The forensic logger is very strict, which means:
CoreDumpDirectory
    configuration).The check_forensic script, which can be found in the
    distribution's support directory, may be helpful in evaluating the
    forensic log output.
See also: Apache Log Files.
Each request is logged two times. The first time before it's processed further (that is, after receiving the headers). The second log entry is written after the request processing at the same time where normal logging occurs.
In order to identify each request, a unique request ID is assigned.
    This forensic ID can be cross logged in the normal transfer log using the
    %{forensic-id}n format string. If you're using
    mod_unique_id, its generated
    ID will be used.
The first line logs the forensic ID, the request line and all received
    headers, separated by pipe characters (|). A sample line
    looks like the following (all on one line):
        +yQtJf8CoAB4AAFNXBIEAAAAA|GET /manual/de/images/down.gif
        HTTP/1.1|Host:localhost%3a8080|User-Agent:Mozilla/5.0 (X11;
        U; Linux i686; en-US; rv%3a1.6) Gecko/20040216
        Firefox/0.8|Accept:image/png, etc...
    
The plus character at the beginning indicates that this is first log line of this request. The second line just contains a minus character and the id again:
      -yQtJf8CoAB4AAFNXBIEAAAAA
    
The check_forensic script takes as its argument the name
    of the logfile. It looks for those +/- ID pairs
    and complains if a request was not completed.
See the security tips document for details on why your security could be compromised if the directory where logfiles are stored is writable by anyone other than the user that starts the server.
Syntax: ForensicLog
    filename|pipe
     Context: server config, virtual
    host
     Module: mod_log_forensic
     Compatibility: Available
    in Version 1.3.30 and above
The ForensicLog directive is used to
    log requests to the server for forensic analysis. Each log entry
    is assigned unique ID which can be associated with the request
    using the normal CustomLog
    directive. mod_log_forensic creates a token called
    forensic-id, which can be added to the transfer log
    using the %{forensic-id}n format string.
The argument, which specifies the location to which the logs will be written, can take one of the following two types of values:
ServerRoot.|", followed by the path
      to a program to receive the log information on its standard
      input. Security: if a program is used, then
      it will be run as the user who started httpd. This will be
      root if the server was started by root; be sure that the
      program is secure. 
    