Apache HTTP Server Version 2.2
Description: | Logging of the requests made to the server |
---|---|
Status: | Base |
Module Identifier: | log_config_module |
Source File: | mod_log_config.c |
This module provides for flexible logging of client requests. Logs are written in a customizable format, and may be written directly to a file, or to an external program. Conditional logging is provided so that individual requests may be included or excluded from the logs based on characteristics of the request.
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
step. The TransferLog
and CustomLog
directives can be used multiple times in each
server to cause each request to be logged to multiple files.
The format argument to the LogFormat
and CustomLog
directives is a string. This string is
used to log each request to the log file. It can contain literal
characters copied into the log files and the C-style control
characters "\n" and "\t" to represent new-lines and tabs.
Literal quotes and backslashes should be escaped with
backslashes.
The characteristics of the request itself are logged by
placing "%
" directives in the format string, which are
replaced in the log file by the values as follows:
Format String | Description | ||||||
---|---|---|---|---|---|---|---|
%% |
The percent sign | ||||||
%a |
Remote IP-address | ||||||
%A |
Local IP-address | ||||||
%B |
Size of response in bytes, excluding HTTP headers. | ||||||
%b |
Size of response in bytes, excluding HTTP headers. In CLF format, i.e.
a '- ' rather than a 0 when no bytes are sent. | ||||||
%{Foobar}C |
The contents of cookie Foobar in the request sent to the server. Only version 0 cookies are fully supported. | ||||||
%D |
The time taken to serve the request, in microseconds. | ||||||
%{FOOBAR}e |
The contents of the environment variable FOOBAR | ||||||
%f |
Filename | ||||||
%h |
Remote host | ||||||
%H |
The request protocol | ||||||
%{Foobar}i |
The contents of Foobar: header line(s)
in the request sent to the server. Changes made by other
modules (e.g. mod_headers ) affect this. If you're
interested in what the request header was prior to when most
modules would have modified it, use mod_setenvif
to copy the header into an internal environment variable and log
that value with the %{VARNAME}e described
above.
| ||||||
%k |
Number of keepalive requests handled on this connection. Interesting if
KeepAlive is being used, so that,
for example, a '1' means the first keepalive request after the initial
one, '2' the second, etc...;
otherwise this is always 0 (indicating the initial request).
Available in versions 2.2.11 and later. | ||||||
%l |
Remote logname (from identd, if supplied). This will return a
dash unless mod_ident is present and IdentityCheck is set
On . | ||||||
%m |
The request method | ||||||
%{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 | ||||||
%{format}p |
The canonical port of the server serving the request or the
server's actual port or the client's actual port. Valid formats
are canonical , local , or remote .
| ||||||
%P |
The process ID of the child that serviced the request. | ||||||
%{format}P |
The process ID or thread id of the child that serviced the
request. Valid formats are pid , tid ,
and hextid . hextid requires APR 1.2.0 or
higher.
| ||||||
%q |
The query string (prepended with a ? if a query
string exists, otherwise an empty string) | ||||||
%r |
First line of request | ||||||
%R |
The handler generating the response (if any). | ||||||
%s |
Status. For requests that got internally redirected, this is
the status of the *original* request --- %>s
for the last. | ||||||
%t |
Time the request was received (standard english format) | ||||||
%{format}t |
The time, in the form given by format, which should be in
strftime(3) format. (potentially localized) | ||||||
%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, not including any query string. | ||||||
%v |
The canonical ServerName
of the server serving the request. | ||||||
%V |
The server name according to the UseCanonicalName setting. | ||||||
%X |
Connection status when response is completed:
(This directive was | ||||||
%I |
Bytes received, including request and headers, cannot be zero.
You need to enable mod_logio to use this. | ||||||
%O |
Bytes sent, including headers, cannot be zero. You need to
enable mod_logio to use this. |
Particular items can be restricted to print only for
responses with specific HTTP status codes by placing a
comma-separated list of status codes immediately following the
"%". For example, "%400,501{User-agent}i"
logs
User-agent
on 400 errors and 501 errors only. For
other status codes, the literal string "-"
will be
logged. The status code list may be preceded by a
"!
" to indicate negation:
"%!200,304,302{Referer}i"
logs Referer
on all requests that do not return one of the three
specified codes.
The modifiers "<" and ">" can be used for requests that
have been internally redirected to choose whether the original
or final (respectively) request should be consulted. By
default, the %
directives %s, %U, %T,
%D,
and %r
look at the original request
while all others look at the final request. So for example,
%>s
can be used to record the final status of
the request and %<u
can be used to record the
original authenticated user on a request that is internally
redirected to an unauthenticated resource.
For security reasons, starting with version 2.0.46,
non-printable and other special characters in %r
,
%i
and %o
are escaped using
\xhh
sequences, where hh
stands for the hexadecimal representation of the raw
byte. Exceptions from this rule are "
and
\
, which are escaped by prepending a backslash, and
all whitespace characters, which are written in their C-style
notation (\n
, \t
, etc). In versions
prior to 2.0.46, no escaping was performed on these strings so
you had to be quite careful when dealing with raw log files.
In httpd 2.0, unlike 1.3, the %b
and
%B
format strings do not represent the number of
bytes sent to the client, but simply the size in bytes of the
HTTP response (which will differ, for instance, if the
connection is aborted, or if SSL is used). The %O
format provided by mod_logio
will log the
actual number of bytes sent over the network.
Note: mod_cache
is implemented as a
quick-handler and not as a standard handler. Therefore, the
%R
format string will not return any handler
information when content caching is involved.
Some commonly used log format strings are:
"%h %l %u %t \"%r\" %>s %b"
"%v %h %l %u %t \"%r\" %>s %b"
"%h %l %u %t \"%r\" %>s %b \"%{Referer}i\"
\"%{User-agent}i\""
"%{Referer}i -> %U"
"%{User-agent}i"
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.
Description: | Buffer log entries in memory before writing to disk |
---|---|
Syntax: | BufferedLogs On|Off |
Default: | BufferedLogs Off |
Context: | server config |
Status: | Base |
Module: | mod_log_config |
Compatibility: | Available in versions 2.0.41 and later. |
The BufferedLogs
directive causes
mod_log_config
to store several log entries in
memory and write them together to disk, rather than writing them
after each request. On some systems, this may result in more
efficient disk access and hence higher performance. It may be
set only once for the entire server; it cannot be configured
per virtual-host.
Description: | Sets filename for the logging of cookies |
---|---|
Syntax: | CookieLog filename |
Context: | server config, virtual host |
Status: | Base |
Module: | mod_log_config |
Compatibility: | This directive is deprecated. |
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.
Description: | Sets filename and format of log file |
---|---|
Syntax: | CustomLog file|pipe
format|nickname
[env= |