Extracting international boundaries from OSM

boundary.ini

# put here the name of keys for ways that are assumed to be polygons if they are closed
# see http://wiki.openstreetmap.org/wiki/Map_Features
closed_ways_are_polygons=aeroway,amenity,boundary,building,craft,geological,historic,landuse,leisure,military,natural,office,place,shop,sport,tourism

# comment to avoid laundering of keys ( ':' turned into '_' )
attribute_name_laundering=yes

# uncomment to report all nodes, including the ones without any (significant) tag
#report_all_nodes=yes

# uncomment to report all ways, including the ones without any (significant) tag
#report_all_ways=yes


[multipolygons]
# common attributes
# note: for multipolygons, osm_id=yes instanciates a osm_id field for the id of relations
# and a osm_way_id field for the id of closed ways. Both fields are exclusively set.
osm_id=yes
osm_version=no
osm_timestamp=no
osm_uid=no
osm_user=no
osm_changeset=no

# keys to report as OGR fields
attributes=name,name:fr,name:en,name:ar,name:es,boundary,border_type,admin_level
# keys that should NOT be reported in the "other_tags" field
ignore=area,created_by,converted_by,source,time,ele,note,openGeoDB:,fixme,FIXME
# uncomment to avoid creation of "other_tags" field
other_tags=no

extract.sh

# Get the planet (38G)
 wget https://ftp5.gwdg.de/pub/misc/openstreetmap/planet.openstreetmap.org/pbf/planet-latest.osm.pbf

# Install Osmium
git clone https://github.com/osmcode/libosmium.git
git clone https://github.com/osmcode/osmium-tool.git
cd osmium-tool/
mkdir build
cd build
cmake ..
make

# Filter boundaries
./osmium tags-filter ../../planet-latest.osm.pbf r/admin_level=2 -o ../../boundary.osm.pbf

# Transform to SHP with ogr2ogr
ogr2ogr --config OSM_CONFIG_FILE boundary.ini -skipfailures boundary.shp  boundaries.osm.pbf -sql "SELECT * FROM multipolygons WHERE admin_level='2'" -lco ENCODING=UTF-8