Well Nominatim != the Rails Port. Nominatim is a name search mechanism for OSM; the rails port is what you’d set up if you wanted to create “your own OpenStreetMap server” - to create a parallel set of OSM data.
Perhaps you could expand a bit on what you’re trying to do?
we are building our own railsport server, instead of using it in cloud. We are downloading North American maps, it is taking very long time. Is it common? Indexing of the stages of the map is taking very long time. Stage 17, it took 6 days to complete. Now we are not Stage 26, which is going to take 60 days or so. Did anyone notice the same?