Anonymize IP logging

[Alexandr Gomoliako]

> I'm not sure if its performance wise, but you can always define your own
> log format http://wiki.nginx.org/HttpLogModule#log_format with a custom
> variable instead of $remote_addr which can be almost anything, try using
> for example http://wiki.nginx.org/HttpLuaModule ngx.md5 or any lua code ;)

Or perl code, which is even easier, than lua :)

    perl_set  $anon_addr  ' sub {
        use Digest::MD5 qw(md5_hex);
        my $r = shift;
        md5_hex $r->remote_addr
    } ';

>> i'm searching for an way to anonymize the ip address in the logfiles