Sometimes you want to send your web server logfiles to someone else, but without revealing confidential information about your web site or visitors. Anonlog enables this by encoding sensitive information, for example hostnames and filenames. It can read logfiles in several different commonly-used formats.

For example, given this logfile: - - [31/Dec/1999:11:11:12 +0000]
  "GET /sample.html HTTP/1.0" 200 1234 "" "Mozilla/4.0" - - [31/Dec/1999:12:11:12 +0000]
  "GET /dir/index.html HTTP/1.0" 200 1234 "" "Mozilla/4.0" - - [31/Dec/1999:15:11:12 +0000]
  "GET /dir/other.html HTTP/1.0" 200 1234 "-" "Mozilla/4.0"
it might produce this anonymized version: - - [31/Dec/1999:11:11:12 +0000]
  "GET /endure.html HTTP/1.0" 200 1234 "" "Mozilla/4.0" - - [31/Dec/1999:12:11:12 +0000]
  "GET /far/index.html HTTP/1.0" 200 1234 "" "Mozilla/4.0" - - [31/Dec/1999:15:11:12 +0000]
  "GET /far/talks.html HTTP/1.0" 200 1234 "-" "Mozilla/4.0"
Anonlog is written by the author of analog, and is licensed under the GNU General Public License. For more details, it's probably easiest just to see the Readme.

Downloading anonlog

The current version of anonlog is 1.0.1. To use it, download either of these two packages: anonlog-1.0.1.tar.gz (36kb) or (38kb).

You also need Perl (at least version 5.004). If you are on Windows and you don't already have Perl, get it free from . If you are on Unix or Linux, you probably already have a new enough Perl, but if not, get it free from .

Anonlog is simple to use, and instructions are in the Readme.


I welcome feedback on this program. Contact me at

Latest version

The latest version is 1.0.1.

Stephen Turner
University of Cambridge Statistical Laboratory

Page last modified: 24-Oct-01