This guide describes how to install and configure an Overpass API server on a Linux machine running Slackware64 15.0. The focus here is on creating a limited-area database initialized from an OSM extract rather than the full planet.

Using a regional extract greatly reduces disk space requirements. The trade-off is that such a database does not support historical functionality (attic data). However, by keeping your database updated with the latest OSM diffs, you can always query up-to-date data for your chosen region.

Setup and updates are explained in files:

• README.setup
• README.update

in the Guide directory.

We assume you:

• Have basic familiarity with the Linux command line.
• Understand OSM data files and their formats.

We’ll use extracts from Geofabrik.de. Their site also explains the available data formats.

The original Overpass developer’s hardware recommendation (maybe outdated) suggested:

• 1 GB RAM
• SSD storage
• 200–300 GB disk space for a full planet database (with meta and attic, full compression)

For modern systems, we recommend:

• 4 GB RAM (minimum)
• Fast SSD or NVMe drive
• 64-bit processor, decent speed

Disk space depends heavily on the region you’re working with (based on the number of OSM objects: nodes, ways, relations).

In this guide, we initialize databases with full metadata and full compression, but without historical (attic) data.

Example sizes after initialization with my op_initial_db.sh script:

        Region               |    File Size       |  Database Size Compressed(gz)
---------------------------------------------------------------------------
arizona-internal.osm.pbf     | 292  MB (0.29 GB)  |    4331 MB (4.3 GB)
california-internal.osm.pbf  | 1324 MB (1.3 GB)   |    9181 MB (9.0 GB)

Rule of thumb: Expect about 10 - 15 GB as an initial database size of a typical region and this size will grow with updates. Allow extra space for the update files.

1. Overpass API

   • Download the latest release here.
   • Use the included overpass.SlackBuild script to compile and install the package.

2. Region OSM Data File

• Download your region’s OSM data file from Geofabrik download server.
• The files are organized geographically — you can select your country, a sub-region, or even a whole continent (depending on your disk space).
• The required format is the common .osm.pbf file with full metadata.
• ⚠️ Do not use .osh.pbf files (these contain historical data, which is not supported in extract-initialized databases).
• Download your region .poly file from Geofabrik which describes the extent of your region. Note that this file is shared between public and internal servers.

3. Osmium Tool

   • Required for converting PBF/other formats to Overpass-compatible XML.
   • Get my SlackBuild from GitHub: osmium-tool_slackbuild.
   • My initialization scripts require Osmium to be installed.

4. Getdiff Program

• My own program written in "c" to download "differs" OSM change files to update database.
• Get the program from my repository.

5. Optional but recommended for OSM work
   • GDAL library
   • JOSM editor
   • QGIS desktop GIS

Originally overpass server was initialed from planet file without historical data. Historical data was accumulated with minutely updates and still being added with the updates. Keeping this fact in mind one can use most of the scripts here to run his / her own instance of overpass server with full planet with meta plus attic data.

Scripts included here assume the following file system structure:

/var/lib/overpass/
      |--- database/
      |--- getdiff/
      |--- logs/
      |--- sources/
      |--- region

where:

/var/lib/overpass: overpass user home directory

/var/lib/overpass/database: where we initial overpass database

/var/lib/overpass/getdiff: getdiff work directory for updating overpass

/var/lib/overpass/logs: overpass scripts log files

/var/lib/overpass/sources: OSM data files used to initial databases

/var/lib/overpass/region: updated OSM data files (extracts) and region change files.

I am NOT an expert on "overpassAPI". Information here may not be accurate, use at your own risk. I mention other websites, they all have rules and there are laws to abide by, read the rules and follow the law please. Be in the know.

Wael Hammoudeh

September 15/2025