How can I use Navmesh data in Server Side?

i have writen an editor plugin which can export the dtNavMesh’s data to file, but seems UE4 doesn’t use the dtTileCache for tile and temp obstacle manage. so even my server loads the dtNavMesh’s data, it still can’t dynamicly add/remove obstacle, i don’t know why UE4 do that on its own, it’s impossible seperated for server usage.