Nginx: How to prevent it from logging local hits

Like any web server, Nginx logs all accesses/hits by default, and if you have some kind of log-based analytics tool (such as AWstats) you probably have it already set to ignore hits from the host itself (usually by skipping both localhost (127.0.0.1) and the server’s public IP address). If you don’t do so, then your statistics will probably be inflated (“wow, my newly created site is surprisingly popular!“), and, unless your site has many regular users, the IP address at the top of the “visitors” table will almost certainly be your own. Local hits can come from several culprits: for instance, some web software such as WordPress or MyBB use special URLs as a form of cron replacement, and also you may have yourself be monitoring your site in some way (such as, in my case, benchmarking a particular URL and MRTGing the access speed).

OK, so your analytics don’t show it anymore — but what about the log files themselves? Maybe you don’t want a large percentage of them being composed of internal hits (especially in the case of those “let’s measure the average response speed for 100 hits every 5 minutes” benchmarks, which for that site made up some 95% of its access logs…). Maybe it even interferes with some other tools you’re using, such as something like DenyHosts or Fail2ban, to detect some abuse patterns, even after whitelisting your external IP. How about having the option not to log them at all? ¹

On Nginx, this is actually pretty easy to do.

1- in the Nginx main configuration file, add the following:

map $remote_addr $notlocal {
        default 1;
        ~^YOUR_EXTERNAL_IP$ 0;
        ~^127.0.0.1$ 0;
}

Replacing YOUR_EXTERNAL_IP with… you can probably guess. 🙂

Important: if your virtual hosts’ configurations are in another directory that is “included” from nginx.conf, take care to add the above before the include lines (e.g. include /etc/nginx/conf.d/*.conf) . Otherwise, the virtual hosts won’t have the “$notlocal” variable defined yet, and Nginx won’t start because of it.

2- for each virtual host where you want to stop logging local hits, edit the access_log line, changing it from something like:

access_log /var/log/nginx/mysite-access.log;

to:

access_log /var/log/nginx/mysite-access.log combined if=$notlocal;

Note the addition of “combined“. “combined” is the default format for Nginx access logs, so specifying it isn’t usually needed, but apparently if you want to specify the “if” condition, it must come after the log format option (otherwise, I guess Nginx thinks you want a log format of “if“, which of course doesn’t exist and will prevent the server from starting.)

That it! Restart Nginx, and enjoy your much cleaner/smaller logs.

1. This isn’t universally desirable; there may be an actual need for logging local hits in your situation, so apply this only where it makes sense for you.