*Note:* these installation instructions are also available in executable
        form for use with vagrant under vagrant/install-on-centos-7.sh.

Installing the Required Software
================================

These instructions expect that you have a freshly installed CentOS version 7.
Make sure all packages are are up-to-date by running:

    sudo yum update -y

The standard CentOS repositories don't contain all the required packages,
you need to enable the EPEL repository as well. To enable it on CentOS,
install the epel-release RPM by running:

    sudo yum install -y epel-release

Now you can install all packages needed for Nominatim:

    sudo yum install -y postgresql-server postgresql-contrib postgresql-devel postgis postgis-utils \
                        git cmake make gcc gcc-c++ libtool policycoreutils-python \
                        php-pgsql php php-pear php-pear-DB libpqxx-devel proj-epsg \
                        bzip2-devel proj-devel geos-devel libxml2-devel boost-devel expat-devel zlib-devel

If you want to run the test suite, you need to install the following
additional packages:

    sudo yum install -y python-pip python-Levenshtein python-psycopg2 \
                        php-phpunit-PHPUnit
    pip install --user --upgrade pip setuptools lettuce==0.2.18 six==1.9 \
                                 haversine Shapely pytidylib


System Configuration
====================

The following steps are meant to configure a fresh CentOS installation
for use with Nominatim. You may skip some of the steps if you have your
OS already configured.

Creating Dedicated User Accounts
--------------------------------

Nominatim will run as a global service on your machine. It is therefore
best to install it under its own separate user account. In the following
we assume this user is called nominatim and the installation will be in
/srv/nominatim. To create the user and directory run:

    sudo useradd -d /srv/nominatim -s /bin/bash -m nominatim

You may find a more suitable location if you wish.

To be able to copy and paste instructions from this manual, export
user name and home directory now like this:

    export USERNAME=nominatim
    export USERHOME=/srv/nominatim

**Never, ever run the installation as a root user.** You have been warned.

Make sure that system servers can read from the home directory:

    chmod a+x $USERHOME

Setting up PostgreSQL
---------------------

CentOS does not automatically create a database cluster. Therefore, start
with initializing the database, then enable the server to start at boot:

    sudo postgresql-setup initdb
    sudo systemctl enable postgresql


Next tune the postgresql configuration, which is located in 
`/var/lib/pgsql/data/postgresql.conf`. See section *Postgres Tuning* in
[the installation page](Installation.md) for the parameters to change.

Now start the postgresql service after updating this config file.

    sudo systemctl restart postgresql


Finally, we need to add two postgres users: one for the user that does
the import and another for the webserver which should access the database
only for reading:


    sudo -u postgres createuser -s $USERNAME
    sudo -u postgres createuser apache


Setting up the Apache Webserver
-------------------------------

You need to create an alias to the website directory in your apache
configuration. Add a separate nominatim configuration to your webserver:

```
sudo tee /etc/httpd/conf.d/nominatim.conf << EOFAPACHECONF
<Directory "$USERHOME/Nominatim/build/website">
  Options FollowSymLinks MultiViews
  AddType text/html   .php
  Require all granted
</Directory>

Alias /nominatim $USERHOME/Nominatim/build/website
EOFAPACHECONF
```




Then reload apache


    sudo systemctl restart httpd


Adding SELinux Security Settings
--------------------------------

It is a good idea to leave SELinux enabled and enforcing, particularly
with a web server accessible from the Internet. At a minimum the
following SELinux labeling should be done for Nominatim:

    sudo semanage fcontext -a -t httpd_sys_content_t "$USERHOME/Nominatim/(website|lib|settings)(/.*)?"
    sudo semanage fcontext -a -t lib_t "$USERHOME/Nominatim/module/nominatim.so"
    sudo restorecon -R -v $USERHOME/Nominatim


Installing Nominatim
====================

Building and Configuration
--------------------------

Get the source code from Github and change into the source directory



    cd $USERHOME
    git clone --recursive git://github.com/twain47/Nominatim.git
    cd Nominatim





The code must be built in a separate directory. Create this directory,
then configure and build Nominatim in there:

    mkdir build
    cd build
    cmake $USERHOME/Nominatim
    make

You need to create a minimal configuration file that tells nominatim
the name of your webserver user and the URL of the website:

```
tee settings/local.php << EOF
<?php
 @define('CONST_Database_Web_User', 'apache');
 @define('CONST_Website_BaseURL', '/nominatim/');
EOF
```


Nominatim is now ready to use. Continue with
[importing a database from OSM data](Import_and_update.md).