-from osmium.replication.server import ReplicationServer
-from osmium import WriteHandler
-
-from ..db import status
-from .exec_utils import run_osm2pgsql
-from ..errors import UsageError
+from nominatim.db import status
+from nominatim.tools.exec_utils import run_osm2pgsql
+from nominatim.errors import UsageError
+
+try:
+ from osmium.replication.server import ReplicationServer
+ from osmium import WriteHandler
+except ModuleNotFoundError as exc:
+ logging.getLogger().fatal("pyosmium not installed. Replication functions not available.\n"
+ "To install pyosmium via pip: pip3 install osmium")
+ raise UsageError("replication tools not available") from exc