Troubleshoot Windows NT network problems with these utilities
IPCONFIG
IPCONFIG is a basic utility for diagnosing problems with TCP/IP, and it also
displays some TCP/IP settings, including IP address, subnet mask, and default
gateway. Using the /all switch with IPCONFIG displays additional information,
such as DNS servers, physical MAC address, DHCP settings, and more. You can also
use the /release and /renew switches to release or renew the IP address lease
from the DHCP server.
NBTSTAT
NBTSTAT displays protocol statistics and current TCP/IP connections using
NetBIOS over TCP/IP (NBT). You can also use NBTSTAT to display registered
NetBIOS names.
NETSTAT
NETSTAT displays even more TCP/IP statistics and connections. If you want to
know which ports are open on your machine, enter netstat -a, and the
system will return a list of all open protocols and remote connections that are
using these ports. You can also display the routing table with netstat
-r, or you can view some TCP/IP statistics using netstat -s.
NSLOOKUP
NSLOOKUP is useful if you have problems with DNS servers or you need to
manually query DNS servers for host records. Advanced users can also list all
records in DNS domains.
PING
PING is the most basic TCP/IP troubleshooting tool. Administrators use it to
make sure they've installed the TCP/IP stack correctly and that the network
connection works. PING uses ICMP Echo requests and replies, which firewalls can
block on some networks. This is why PING times out even when the connection with
a remote machine works.