It is possible to create old indices and to use them for searching further on.

[settings]
GeoDbIndexing= Create

If you set GeoDbIndexing to Convert, the old indices will continue to be generated and then converted into the GeoDb.

[settings]
UseGeoDbForGeoSearch= 1

If you set UseGeoDbForGeoSearch to 0, the directory geoindexv2 will continue to be used for the geo search and the old index will be created during index generation, even if GeoDbIndexing=Create.