Databases, Systems & Networks

The mod_geoip2 module embeds GeoIP database lookups into the Apache web server. It is only capable of looking up the IP of a client that connects to the web server, as opposed to looking up arbitrary addresses.

This module works with Apache 2. Please use mod_geoip with Apache 1.

Installation

You may download the latest release of mod_geoip2 or get the latest development version from GitHub. See the included INSTALL file in the tarball for installation details.

Overview

The mod_geoip2 module uses the libGeoIP library to look up geolocation information for a client as part of the http request process. This module is free software, and is licensed under the Apache license.

To compile and install this module, you must first install libGeoIP 1.4.3 or newer.

The mod_geoip2 module takes effect either during request header parsing phase or the post read request phase, depending on whether it is configured for server-wide use or for a specific location/directory.

When enabled, the module looks at the incoming IP address and sets some variables which provide geolocation information for that IP. The variables it set depend on the specific GeoIP database being used (Country, City, ISP, etc.). These variables can be set in either the request notes table, the environment or both depending on the server configuration.

Configuration

GeoIP configuration directives can be placed in either an .htaccess file or in the main server config. After installing the module, make sure that

GeoIPEnable On

is set in your Apache configuration file. This will call the GeoIP Country database from its default location (e.g. /usr/local/share/GeoIP/GeoIP.dat)

If you want to specify options, for example to use a different database or to pass caching options, you can use the GeoIPDBFiledirective:

File and Caching Directives

GeoIPDBFile /path/to/GeoIP.dat [GeoIPFlag]

For example:

GeoIPDBFile /usr/local/share/GeoIP/GeoIP.dat MemoryCache
GeoIPDBFile /usr/local/share/GeoIP/GeoIPOrg.dat Standard

The default GeoIPFlag value is Standard, which does not perform any caching, but uses the least memory. To turn on memory caching use:

GeoIPDBFile /path/to/GeoIP.dat MemoryCache

The memory cache option can use a large amount of memory. We recommend that you use Memory Caching only for the smaller database files, such as GeoIP Country and GeoIP ISP.

Another MemoryCache option is MMapCache, which uses the the mmap system call to map the database file into memory.

If you would like the API to check to see if your local GeoIP files have been updated, set the CheckCache flag:

GeoIPDBFile /path/to/GeoIP.dat CheckCache

Before making a call to the database, geoip will check the GeoIP.dat file to see if it has changed. If it has it, then it will reload the file. With this option, you do not have to restart Apache when you update your GeoIP databases.

If you would like to turn on partial memory caching, use the IndexCache flag:

GeoIPDBFile /path/to/GeoIP.dat IndexCache

The IndexCache option caches the most frequently accessed index portion of the database, resulting in faster lookups than StandardCache, but less memory usage than MemoryCache. This is especially useful for larger databases such as GeoIP Organization and GeoIP City. For the GeoIP Country, Region and Netspeed databases, setting the IndexCache option just causes the C API to use the MemoryCache.

Currently, multiple GeoIPFlags options can not be combined.

Enabling UTF-8 Output

You may change the output charset from ISO-8859-1 (Latin-1) to UTF-8 with this directive:

GeoIPEnableUTF8 On

By default mod_geoip2 sets variables in both the notes table and environment. For performance reasons you may want to set only the one you use. To do so, use the GeoIPOutput configuration directive:

Output Variable Location

GeoIPOutput Notes   # Sets the Apache notes table only
GeoIPOutput Env     # Sets environment variables only
GeoIPOutput All     # Sets both (default behaviour)

Proxy-Related Directives

By default, this module will simply look at the IP address of the client. However, if the client is using a proxy, this will be the address of the proxy. You can use the GeoIPScanProxyHeaders directive to look at proxy-related headers.

GeoIPScanProxyHeaders On

When this is set, the module will look at several other sources for the IP address, in this order:

• The HTTP_CLIENT_IP environment variable (set by Apache).
• The HTTP_X_FORWARDED_FOR environment variable (set by Apache).
• The X-Forwarded-For for header (set by a proxy).
• The HTTP_REMOTE_ADDR environment variable (set by Apache).

This module will use the first IP address it finds in one of these locations instead of the IP address the client connected from.

Some of these variables may contain a comma-separate list of IP addresses (when a client goes through multiple proxies). In this case, the default behavior is to use the first IP address. You can set the GeoIPUseLastXForwardedForIP directive to use the last address instead:

GeoIPUseLastXForwardedForIP On

Output Variables

As noted above, these variables can be set in either the Apache request notes table, the environment, or both. The specific variables which are set depend on the database you are using.

GeoIP Country Edition Output Variables

GeoIP Region Edition Output Variables

GeoIP City Edition Output Variables

GeoIP ISP Edition Output Variables

GeoIP Organization Edition Output Variables

GeoIP Netspeed Edition Output Variables

GeoIPv6 Edition (experimental) Output Variables

Examples

Here are some examples of how you can use mod_geoip2.

Redirecting a client based on country

This example show you how to redirect a client based on the country code that GeoIP sets.

GeoIPEnable On
GeoIPDBFile /path/to/GeoIP.dat

# Redirect one country
RewriteEngine on
RewriteCond %{ENV:GEOIP_COUNTRY_CODE} ^CA$
RewriteRule ^(.*)$ http://www.canada.com$1 [R,L]

# Redirect multiple countries to a single page
RewriteEngine on
RewriteCond %{ENV:GEOIP_COUNTRY_CODE} ^(CA|US|MX)$
RewriteRule ^(.*)$ http://www.northamerica.com$1 [R,L]

Blocking a client based on country

This example show you how to block clients based on the country code that GeoIP sets.

GeoIPEnable On
GeoIPDBFile /path/to/GeoIP.dat

SetEnvIf GEOIP_COUNTRY_CODE CN BlockCountry
SetEnvIf GEOIP_COUNTRY_CODE RU BlockCountry
# ... place more countries here

Deny from env=BlockCountry

Allowing clients based on country

This example show you how to allow only clients from specific countries.

GeoIPEnable On
GeoIPDBFile /path/to/GeoIP.dat

SetEnvIf GEOIP_COUNTRY_CODE US AllowCountry
SetEnvIf GEOIP_COUNTRY_CODE CA AllowCountry
SetEnvIf GEOIP_COUNTRY_CODE MX AllowCountry
# ... place more countries here

Deny from all
Allow from env=AllowCountry

Server vs Directory context

All directives except GeoIPEnable are server config only, i.e., you type it only once per server config. Otherwise the latest wins.

<IfModule mod_geoip.c>
  GeoIPEnable Off
  GeoIPEnableUTF8 On
  GeoIPOutput Env
  GeoIPDBFile /usr/local/share/GeoIP/GeoIP.dat MemoryCache
  GeoIPDBFile /usr/local/share/GeoIP/GeoIPCity.dat MemoryCache
  GeoIPDBFile /usr/local/share/GeoIP/GeoIPOrg.dat MemoryCache
</IfModule>

GeoIPEnable is useful in server or directory context. For example:

GeoIP is only available for a specific location:

<IfModule mod_geoip.c>
  GeoIPEnable Off
  GeoIPEnableUTF8 On
  GeoIPOutput Env
  GeoIPDBFile /usr/local/share/GeoIP/GeoIP.dat MemoryCache
</IfModule>

# GeoIP information is avail only inside /xxx
<Location /geoip-enabled>
  GeoIPEnable On
  ...
</Location>

<Location /other>
  ...
</Location>

GeoIP is available for all locations:

<IfModule mod_geoip.c>
  GeoIPEnable On
  GeoIPEnableUTF8 On
  GeoIPOutput Env
  GeoIPDBFile /usr/local/share/GeoIP/GeoIP.dat MemoryCache
</IfModule>

# This doesn't work, because it's already been enabled in the server-wide
# config!
<Location /geoip-enabled>
  GeoIPEnable On
</Location>

<Location /geoip-disabled>
  GeoIPEnable Off
</Location>

Memory Usage

Starting at mod_geoip2 version 1.2.1, all Apache child processes share the same database when you set the MemoryCache or MMapCache flag.

Memory usage is about the same as the database file size, no matter how many child processes Apache spawns. The only thing to remember is ask Apache to update if your database changes. Use the graceful restart option to do so without stopping Apache.

Performance

For improved performance, you may want to enable mod_geoip only for specific HTML pages. If you want to use the mod_geoip module site-wide, you may still be able to only use it for HTML pages and not images. To restrict the pages where mod_geoip2 is used, place the GeoIPEnable On directive inside a , or directive, see: httpd.apache.org/docs/2.0/sections.html

Troubleshooting

If the module is not working, make sure that the httpd user (e.g. nobody) has read access to the GeoIP database file(s) you are using.

If the GeoIP variables do not show up please make sure that the client IP address is not on a private network such as 10.0.0.0/8, 172.16.0.0/12 or 192.168.0.0/16. GeoIP can only look up public IP addresses.