Web server log analysis has become the need of the time. With its growing importance, new tools have been invented which have made maintaining log files easy. At older times, one had to be sitting on continuous watch on the web server for tracking the web traffic. But now, installing software, all your web server traffic can be monitored and log files can be maintained. Maintaining these log files is very important as one has to be very alert as to what files are sent and received through the web server, what data is been accessed from the web and also, who all are logging in the web server? To maintain a track of all this and much more, you need a web server log file analyzer. Both these, Webalizer and Awstats, are web server log files analyzers which provide excellent facilities and are for free!!! Let us look at both these little comparative way.

Webalizer helps in producing very detailed and easy to configure reports which are in HTML format which can be viewed with a standard browser. Some of the features include:

1. Language used to develop it is C, so it is very fast and is portable. For example, they claim that on simple 1.6GHz processor, Webalizer can analyze about 70000 records per second.
2. It handles variety of log files formats such as common log files (CLF), number of various NCSA combined log files formats, wuftpd, xferlog which come under FTP, squid server formats, W3C extended log formats and many more. In addition to this, .gz and .bz2 formats are also supported. These are compressed logs and can be directly without uncompressing them with the help of Webalizer.
3. The reports that are generated can be configured from command line also. The detailed information about this configuration can be obtained in README files.
4. It supports multiple languages with languages such as Serbian, Slovene, Turkish, Ukrainian, Malay, Icelandic and many more which are not in frequent use in international market.
5. Unlimited size of the log files is supported and the data can be rotated so that there's no need to keep huge sized files.
6. Full support is available for IPv4 and IPv6.

Now let us look at the features provided by Awstats:

1. It shows the number of visits by with the visit time and also number of some unique visitors.
2. Statistics about the authenticated users.
3. Domains and countries of the visitors.
4. The entry and exit pages which are most viewed.
5. Multiple file types are supported.
6. Various web compression statistics are also viewed which prove to be very useful.
7. The OS used by the visitors.
8. The various browsers that are used by the visitors.
9. Important characteristic is that it shows the worm attacks and possible threats to your web server.
10. It also displays the HTTP errors.
11. For servers which are load balanced, cluster reports are generated.

Many such features are included in both of them. But comparing both of them on basis of number services offered and reliability, one may suggest to go for Awstats.