Use ipconfig to inspect Windows network settings, ping to test ICMP reachability, nslookup to test DNS, and tracert or mtr to examine responses along a route. These commands answer different questions: no ping reply does not necessarily mean a device is offline, a successful DNS lookup does not prove an app is working, and a route trace may omit routers that do not answer probes.
Choose a command by the question you need answered
| Command | Question it helps answer | How to interpret its limits |
|---|---|---|
ipconfig (Windows) |
What IP configuration and default gateway does Windows show? | Use the active adapter’s details; Microsoft uses this command to locate the gateway in its Wi-Fi troubleshooting guidance. |
ping <host> |
Does the target return ICMP echo replies from this computer? | ICMP may be blocked by a firewall or network policy. Silence alone does not establish that the target is down; see Microsoft’s DNS client troubleshooting guidance. |
nslookup <name> |
Can DNS resolve a name, and does the selected DNS server respond? | Test the server and the specific name separately. A successful lookup does not verify that the destination’s application is healthy; Microsoft’s DNS guide covers this distinction. |
tracert <host> (Windows) |
Which intermediate routers return responses to Windows route-trace probes? | Windows increases the probe’s TTL to expose responding hops. Some routers silently discard expired probes, leaving gaps; see Microsoft’s TRACERT explanation. |
mtr <host> (Linux distributions where installed) |
What response percentages and timings appear over repeated probes along the route? | MTR combines traceroute-style path discovery with ping-like observations. Options vary by distribution and version; consult the Ubuntu Jammy mtr manual. |
ipconfig /displaydnsipconfig /flushdns (Windows) |
What DNS records are in the local cache, and can that cache be cleared? | Microsoft lists these commands in a workflow for cached DNS responses. Clearing the cache does not fix an unrelated connectivity or service problem. |
Run the checks in a useful order
This is a practical sequence, not a universal or officially prescribed triage standard. Start by recording the symptom: note whether one service, one device, or multiple devices are affected, and whether the failure is intermittent or persistent.
- Inspect the Windows configuration. Open Command Prompt or PowerShell and run
ipconfig. Identify the active adapter and its default gateway. If the adapter is disconnected or lacks the expected address or gateway, investigate the local connection or configuration before drawing conclusions from tests to remote hosts. - Test the local gateway. Run
ping <default-gateway-address>, replacing the placeholder with the gateway shown byipconfig. A reply confirms that the gateway returned ICMP echo replies from this vantage point. No reply may indicate filtering, so it is not by itself proof that the router is unavailable. - Test a remote IP address, if you have an appropriate target. Run
ping <remote-IP-address>. If the gateway responds but the remote target does not, the problem may lie farther along the path—or the remote network may simply block ICMP. Compare with other evidence rather than treating a timeout as a definitive outage. - Test name resolution separately. Run
nslookup <name>, substituting the hostname that fails. To test a particular DNS server, usenslookup <name> <DNS-server-address>. A DNS response helps distinguish name-resolution trouble from a failure to reach a service by IP, but does not establish that the service itself accepts connections. - Inspect the responding route when the remote destination is slow or unreachable. On Windows, run
tracert <host>. On a Linux system with MTR installed, runmtr <host>. Review which probes receive replies and where responses change; do not assume that the last visible hop is the point of failure. - Check the Windows DNS cache if the name still fails. Run
ipconfig /displaydnsto inspect cached records. If a stale or negative cached response is a plausible cause, runipconfig /flushdns, then retry the lookup. Useipconfig /renewonly when renewing a dynamically assigned address is appropriate to the situation; it is not a general DNS or connectivity fix.
What each result does—and does not—tell you
Ping: ICMP reachability, not application health
ping sends ICMP echo requests and reports whether echo replies return. A reply shows that the target or an intermediate network device responded to that probe; it does not prove that a website, game, or other application is functioning. Conversely, a timeout may reflect firewall or policy filtering even when other traffic works. Microsoft specifically notes that ICMP must be allowed through the firewall for ping-based testing to work.
Tracert: responding hops, not a complete network map
Windows tracert sends probes with progressively increasing time-to-live (TTL) values. When a probe expires, a router may return a response that identifies that hop. A router that silently drops expired probes will not appear as a responding hop, so an asterisk or gap is not proof that the router is broken. The output describes responses to this trace from your location and with its probe type, not every route or all traffic behavior.
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Nslookup: DNS answers, not end-to-end service checks
nslookup helps determine whether a DNS server responds and whether a requested name resolves. When diagnosing a failure, separate the question “Can I reach the DNS server?” from “Does this server return the record for the failing name?” A successful answer only establishes that DNS supplied a result; it does not confirm that the destination host or application is reachable.
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When to use extended diagnostics on Cisco devices
On Cisco network devices, extended ping and extended traceroute provide additional ways to investigate connectivity and narrow routing problems. They are device-context tools rather than drop-in replacements for the Windows commands above: available options and the meaning of a test depend on the device and how it is configured. Follow the applicable Cisco platform guidance, including Cisco’s explanation of extended ping and traceroute, before using them to draw conclusions about a path.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.Platform and syntax notes
The examples above label Windows commands explicitly and identify MTR as a Linux tool where installed. Command availability and options depend on operating system, distribution, and version. The command names may look familiar across systems, but the examples here do not establish a complete Windows/macOS/Linux syntax comparison; check the relevant platform’s documentation before relying on other options.
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