The Windows Network Command Line

Overview

This lecture covers essential Windows networking commands for troubleshooting, including IP address discovery, connectivity testing, route tracing, and network shares management.

Viewing Network Configuration

• Use the ipconfig command to display adapter, IP, subnet mask, DNS, and DHCP server information for IPv4 and IPv6.
• ipconfig /all provides more detailed network configuration, including host name and proxy settings.

Testing Network Connectivity

• The ping command checks communication with another network device and measures round trip times.
• Windows ping sends four data packets and reports any packet loss and round trip speed.
• The TTL (Time to Live) value in ping shows remaining hops, helping diagnose route changes.

Analyzing Active Connections

• netstat displays active connections and listening ports.
• netstat -a lists all connections and listening ports on the device.
• netstat -b shows the executable responsible for each connection (requires administrator rights).
• netstat -n displays connections using only IP addresses without name resolution.

DNS Resolution

• Use nslookup to resolve domain names to IP addresses and view DNS server responses.
• Multiple IPs may appear for redundancy if a domain has several servers.

Managing Windows Networks and Shares

• Windows net commands manage resources like user accounts and shared files.
• net view \\servername lists available shares on a remote server.
• net use [drive:] \\servername\sharename maps a shared drive to a drive letter.
• net user views and manages user accounts on a device.

Tracing Network Paths

• tracert traces the route packets take to reach a destination, listing each router (hop) along the way.
• TTL in tracert refers to the number of routers a packet can traverse, not actual time.
• Some routers or firewalls may not respond, resulting in missing data for certain hops.

Combined Path and Ping Analysis

• pathping combines ping and tracert, first mapping the route and then measuring round trip times and packet loss at each hop.
• pathping takes longer but gives detailed hop-by-hop network performance statistics.

Key Terms & Definitions

• IP Address — Unique identifier for a device on a network.
• Subnet Mask — Determines the network and host portions of an IP address.
• DNS (Domain Name System) — Translates domain names to IP addresses.
• DHCP (Dynamic Host Configuration Protocol) — Assigns IP address settings automatically.
• TTL (Time to Live) — Limits the number of hops a packet can make.
• Ping — Tests connectivity between devices.
• Traceroute (tracert) — Maps the path packets take to a destination.
• Netstat — Displays network connections and listening ports.
• nslookup — Queries DNS for domain resolution.

Action Items / Next Steps

• Practice using ipconfig, ping, netstat, nslookup, tracert, and pathping commands.
• Try mapping a shared network drive with net use.
• Review details from ipconfig /all for your device's configuration.