Networking fundamentals

Network Troubleshooting Tools

Overview

These tools are the first things reached for when something on a network isn't working — knowing them well speeds up both helpdesk work and later SOC investigation.

Key concepts

  • ipconfig/ifconfig
  • ping, tracert/traceroute
  • nslookup
  • netstat, ARP
  • Wireshark

Tools & techniques

ToolPurposeWhen to use
WiresharkPacket capture and protocol inspectionDeep-dive traffic analysis
pingBasic reachability testFirst troubleshooting step
nslookupDNS lookupsDiagnosing name-resolution issues

How it works

Network troubleshooting is the process of identifying and resolving connectivity issues. Start with basic physical checks, then move systematically through the networking layers.

ToolPurposeWhen to use
ipconfigDisplays Windows network configuration (IP, subnet mask, gateway, DNS)First step in most Windows network issues
pingTests whether a device can reach another network destinationBasic connectivity check
tracertShows the route traffic takes to a destination (Windows)Identifying where along a path traffic is failing
tracerouteSame as tracert, for Linux/macOSSame as above, non-Windows systems
nslookupChecks DNS informationDiagnosing DNS-resolution problems
netstatDisplays active connections, listening ports, protocol statsIdentifying what's communicating over the network
ARPLinks local IP addresses to MAC addressesViewing IP-to-MAC mappings
WiresharkCaptures and inspects network trafficDeep protocol analysis, monitoring, security investigations