Before Windows 2000, Microsoft networking relied heavily on NetBIOS (Network Basic Input/Output System) over TCP/IP. NBT uses three distinct services, each on specific ports:
| Error | Likely Cause | Solution | |-------|--------------|----------| | bind failed on port 170: Address already in use | Another process (e.g., a second nmbd) owns the port | sudo lsof -i :170 to find and stop the conflict | | Clients cannot browse but can connect to shares | Datagram port mismatch or firewall blocking UDP 170 | Check iptables -L and client config | | smbd logs: Can't become connected master browser | Election packets lost on non-standard port | Ensure all potential master browsers use the same datagram port | smbd 170