All MS Windows machines employ an in-memory buffer in which is
stored the NetBIOS names and IP addresses for all external
machines that machine has communicated with over the
past 10 to 15 minutes. It is more efficient to obtain an IP address
for a machine from the local cache than it is to go through all the
configured name resolution mechanisms.
If a machine whose name is in the local name cache is shut
down before the name is expired and flushed from the cache, then
an attempt to exchange a message with that machine will be subject
to timeout delays. Its name is in the cache, so a name resolution
lookup will succeed, but the machine cannot respond. This can be
frustrating for users but is a characteristic of the protocol.
The MS Windows utility that allows examination of the NetBIOS
name cache is called “nbtstat.” The Samba equivalent