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Use ipconfig to inspect a Windows device’s network settings, ping to test ICMP reachability, nslookup to check DNS, and tracert or mtr to examine responding hops along a route. These commands answer different questions: no single result proves that an entire network or application is healthy.
Which command should you use?
| Command | Question it helps answer | How to interpret it |
|---|---|---|
ipconfig (Windows) |
What IP configuration and default gateway does Windows show? | Use the output to identify the active adapter and its gateway. Microsoft’s Wi-Fi guidance uses ipconfig for this check: Fix Wi-Fi connection issues in Windows. |
ping <host> |
Does the target return ICMP echo replies from this device? | A reply confirms a response to that ICMP probe, not application health. Silence can mean filtering as well as a connectivity problem. |
nslookup <name> |
Can DNS resolve this name, and does the selected DNS server respond? | Test the server and the failing name separately when diagnosing DNS. |
tracert <host> (Windows) |
Which intermediate routers return responses to Windows route-tracing probes? | Some routers do not respond to expired probes, so the output may contain gaps. |
mtr <host> (Linux systems with MTR installed) |
What response rates and timings appear across repeated probes along a route? | MTR combines traceroute-like and ping-like behavior. Options and availability vary by distribution and version. |
ipconfig /displaydns and ipconfig /flushdns (Windows) |
What DNS entries are cached locally, and can the cache be cleared? | Use these when a stale or cached response is a plausible cause of a name-resolution problem. |
How to troubleshoot a connection in a useful order
Start by noting what fails and how widely it fails: one website or service, one device, or several devices. This is a practical sequence, not a universal diagnostic standard. Run commands from the affected device so their results reflect its network path.
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- Inspect local settings (Windows): open Command Prompt or PowerShell and run
ipconfig. Find the adapter in use and note its IP address and default gateway. If the adapter is disconnected or has no usable configuration, investigate that local connection before interpreting remote tests. - Test the gateway: run
ping <default-gateway-address>, substituting the gateway shown byipconfig. A response shows that the gateway answered ICMP from this device. No response is inconclusive because ICMP may be blocked. - Test a remote IP address: if appropriate, run
ping <known-remote-IP>. This tests ICMP reachability without first relying on a DNS lookup. Choose a destination expected to answer ICMP; some hosts and networks filter it. - Check name resolution separately: run
nslookup <name>, replacing<name>with the hostname that fails. If needed, query a specific DNS server withnslookup <name> <DNS-server-address>. Compare whether the server responds and whether it returns an answer for the failing name. Microsoft’s workflow separates testing DNS-server connectivity from testing resolution of a record: Troubleshooting DNS clients. - Inspect the route if the remote destination is unreachable or slow: on Windows, run
tracert <host>. On a system where MTR is installed, runmtr <host>. These show responses from probes along the path; they do not guarantee that every router will be visible. - Consider the Windows DNS cache: run
ipconfig /displaydnsto inspect cached entries. If a stale cache is a plausible cause,ipconfig /flushdnsclears it; then retry the lookup. Useipconfig /renewonly when renewing a dynamically assigned address is appropriate, not as a generic fix for every connectivity fault.
What each command can—and cannot—tell you
ipconfig: inspect the Windows device’s settings
ipconfig reports Windows IP configuration. For a basic check, identify the active adapter and default gateway, then use the gateway address as a target for a local reachability test. Microsoft’s instructions use the command to find the gateway when checking Wi-Fi connectivity: Fix Wi-Fi connection issues in Windows.
ping: test ICMP response, not a complete service
ping <host> sends ICMP echo probes and reports whether replies arrive. A successful reply shows that the target (or a device responding on its behalf) answered those probes from your vantage point. It does not establish that a web page, application port, login, or other service works.
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A failed ping is not proof that the host is offline. Firewalls or network policy can block ICMP; Microsoft notes that ICMP must be allowed through the firewall for this test to work. Use other evidence, such as DNS results or a route trace, before drawing a conclusion: Troubleshooting DNS clients.
nslookup: isolate DNS resolution
nslookup <name> asks a DNS server to resolve a hostname. It helps distinguish a name-resolution failure from a problem reaching an IP address, but a successful answer does not prove that the destination’s application is running or reachable on the required service.
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If a lookup fails, test whether the DNS server responds and whether the particular failing name resolves. On Windows, ipconfig /displaydns shows cached DNS entries and ipconfig /flushdns clears the cache. Microsoft includes these checks in its DNS troubleshooting guidance, including cases involving cached negative responses: Troubleshooting DNS clients.
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Windows tracert <host> sends probes with incrementally increasing time-to-live (TTL) values. When a router returns a response as a probe expires, that hop can appear in the output. A router that silently drops expired probes may not appear, so an asterisk or missing hop is not by itself proof of a broken router or route. See Microsoft’s explanation of the command and its behavior: Use TRACERT to Troubleshoot TCP/IP Problems.
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mtr: combine repeated route and response observations
MTR combines traceroute-like path discovery with repeated ping-like probes. Its output can show response percentages and response times at points along the route, which can help reveal patterns that a single route trace may not show. It remains dependent on which probes receive replies, so filtering or rate limiting can affect the display. The Ubuntu Jammy manual documents MTR’s behavior and options: mtr manual. Cloudflare also identifies MTR as a troubleshooting method for path health: Gathering information for troubleshooting sites.
How to read route-trace gaps and delays
- A hop responds: that device returned a response to the probe. It does not prove that all traffic beyond it is healthy.
- A hop does not respond: the probe may have been filtered, ignored, or rate-limited. Microsoft notes that some routers silently drop probes whose TTL expires, creating gaps in
tracertoutput. - Later hops respond after a gap: the route continues beyond the nonresponding hop; the gap alone does not identify a fault.
- Repeated high response times or loss: treat them as clues, not a definitive diagnosis. A router may handle diagnostic probes differently from ordinary application traffic, and results describe the path and probe type from the device running the command.
Windows route tracing uses TTL behavior and can produce incomplete paths when intermediate routers do not respond: Microsoft’s TRACERT guidance. For router-side investigation, Cisco documents extended ping and traceroute commands that let network administrators investigate connectivity and narrow routing problems; the available options depend on device context: Understand the Extended Ping and Extended Traceroute Commands.
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Common result patterns
The gateway does not reply to ping
First verify that ipconfig shows the expected active adapter and gateway. A missing reply may indicate a local connectivity issue, but it can also mean the gateway or network policy does not answer ICMP. Do not infer an outage from that result alone.
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A remote IP responds, but a hostname does not work
Check the name with nslookup. If resolution fails, investigate the DNS server, the specific record, and—on Windows—the local cache. If the name resolves but the application still fails, DNS is not the only issue to investigate.
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The hostname resolves, but ping gets no reply
DNS may be working while ICMP is filtered, or the destination may not respond to echo requests. A successful lookup and failed ping are not contradictory: they test different things.
tracert shows asterisks or missing hops
Those entries mean the probes did not receive the expected response within the wait period. Intermediate devices may suppress or limit such responses. Check whether later hops respond and compare with the actual application symptom rather than treating each gap as a fault.
Platform and syntax notes
The command examples above are explicitly labeled for Windows or Linux where supported. Windows uses tracert; MTR is a separate utility documented for Ubuntu Jammy and may need to be installed. Other operating systems and versions can use different command names, options, or defaults. Cisco extended diagnostics run in network-device contexts and are not interchangeable with a desktop command prompt.
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