I am running my own DNS on my local router for some hostnames in my LAN. The DNS is working but from time to time windows loses the resolving. If I access my NAS for instance it happens, that I can load it's web GUI at its LAN FQDN but after a few reloads, Chrome tells me that the hostname is not found. When I type nslookup into cmd, I get a response from my router but pinging that hostname gives an error still that the name was not resolved. A few attempts later, I can ping again and also access the GUI of the NAS. Why does this happen and how can I tell Windows to either keep the resolving or ask the router again when a name is not found in cache?