+Change into the project directory and run the following command:
+
+ bash update_database.sh
+
+This will get diffs from the replication server, import diffs and index
+the database. The default replication server in the
+script ([Geofabrik](https://download.geofabrik.de)) provides daily updates.
+
+## Using an external PostgreSQL database
+
+You can install Nominatim using a database that runs on a different server when
+you have physical access to the file system on the other server. Nominatim
+uses a custom normalization library that needs to be made accessible to the
+PostgreSQL server. This section explains how to set up the normalization
+library.
+
+!!! note
+ The external module is only needed when using the legacy tokenizer.
+ If you have chosen the ICU tokenizer, then you can ignore this section
+ and follow the standard import documentation.
+
+### Option 1: Compiling the library on the database server
+
+The most sure way to get a working library is to compile it on the database
+server. From the prerequisites you need at least cmake, gcc and the
+PostgreSQL server package.
+
+Clone or unpack the Nominatim source code, enter the source directory and
+create and enter a build directory.
+
+```sh
+cd Nominatim
+mkdir build
+cd build
+```
+
+Now configure cmake to only build the PostgreSQL module and build it:
+
+```
+cmake -DBUILD_IMPORTER=off -DBUILD_API=off -DBUILD_TESTS=off -DBUILD_DOCS=off -DBUILD_OSM2PGSQL=off ..
+make
+```
+
+When done, you find the normalization library in `build/module/nominatim.so`.
+Copy it to a place where it is readable and executable by the PostgreSQL server
+process.
+
+### Option 2: Compiling the library on the import machine
+
+You can also compile the normalization library on the machine from where you
+run the import.
+
+!!! important
+ You can only do this when the database server and the import machine have
+ the same architecture and run the same version of Linux. Otherwise there is
+ no guarantee that the compiled library is compatible with the PostgreSQL
+ server running on the database server.
+
+Make sure that the PostgreSQL server package is installed on the machine
+**with the same version as on the database server**. You do not need to install
+the PostgreSQL server itself.
+
+Download and compile Nominatim as per standard instructions. Once done, you find
+the normalization library in `build/module/nominatim.so`. Copy the file to
+the database server at a location where it is readable and executable by the
+PostgreSQL server process.
+
+### Running the import
+
+On the client side you now need to configure the import to point to the
+correct location of the library **on the database server**. Add the following
+line to your your `.env` file:
+
+```php
+NOMINATIM_DATABASE_MODULE_PATH="<directory on the database server where nominatim.so resides>"
+```
+
+Now change the `NOMINATIM_DATABASE_DSN` to point to your remote server and continue
+to follow the [standard instructions for importing](Import.md).
+
+
+## Moving the database to another machine
+
+For some configurations it may be useful to run the import on one machine, then
+move the database to another machine and run the Nominatim service from there.
+For example, you might want to use a large machine to be able to run the import
+quickly but only want a smaller machine for production because there is not so
+much load. Or you might want to do the import once and then replicate the
+database to many machines.
+
+The important thing to keep in mind when transferring the Nominatim installation
+is that you need to transfer the database _and the project directory_. Both
+parts are essential for your installation.
+
+The Nominatim database can be transferred using the `pg_dump`/`pg_restore` tool.
+Make sure to use the same version of PostgreSQL and PostGIS on source and
+target machine.
+
+!!! note
+ Before creating a dump of your Nominatim database, consider running
+ `nominatim freeze` first. Your database looses the ability to receive further
+ data updates but the resulting database is only about a third of the size
+ of a full database.
+
+Next install Nominatim on the target machine by following the standard installation
+instructions. Again, make sure to use the same version as the source machine.
+
+Create a project directory on your destination machine and set up the `.env`
+file to match the configuration on the source machine. Finally run