Step-by-Step Network Diagnosis Commands | Generated by AI
Here’s the command-by-command breakdown of how I diagnosed it:
STEP-BY-STEP NETWORK DIAGNOSIS
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1. TRACEROUTE (failed — hops block ICMP)
$ traceroute -w 2 -m 10 192.168.1.36
Result: all timeouts (local LAN routers don't respond to traceroute)
2. PING 10x TO .36 — check consistency
$ ping -c 10 192.168.1.36 | tail -5
Result: min/avg/max = 6.6/16.4/75.0ms, stddev 19.7ms
Insight: big range (6ms to 75ms) — that's WiFi jitter, not path latency
3. COMPARE ROUTER VS WORKSTATION (5 pings each)
$ ping -c 5 192.168.1.1 | grep round-trip
$ ping -c 5 192.168.1.36 | grep round-trip
Result: router avg 18.8ms, workstation avg 25.0ms
Insight: router has similar jitter — WiFi is the common bottleneck
4. CHECK WHICH INTERFACE IS ACTIVE
$ ifconfig en0 | grep -E "status|inet"
Result: en0 is active, IP 192.168.1.52 — confirmed on Wi-Fi
5. CHECK ARP TABLE — see MAC addresses of neighbors
$ arp -a | grep "192.168.1\.(1|36)"
Result: both on en0 (same LAN), .36 MAC = 4:7c:16:d9:54:5b
Insight: 4:7c:16 is ASRock (your workstation motherboard)
6. CHECK WIFI HARDWARE INFO (tried, deprecated on newer macOS)
$ /System/Library/PrivateFrameworks/Apple80211.framework/.../airport -I
$ wdutil info
Result: both failed/need sudo on macOS 14+
7. 30 PINGS TO .36 — better statistics
$ ping -c 30 192.168.1.36 | grep round-trip
Result: min/avg/max = 4.4/12.4/69.5ms, stddev 15.8ms
Insight: average is only 12ms — the 92ms was an outlier spike
COMMANDS SUMMARY:
ping -c N <host> | grep round-trip — latency stats
ping -c 10 <host> | tail -5 — quick consistency check
ifconfig en0 | grep inet — confirm your IP/interface
arp -a | grep <ip> — see MAC + which interface
traceroute <host> — path hops (often blocked LAN)
networksetup -listallhardwareports — list all interfaces
The key trick: compare the router ping to the target ping. If both show similar jitter, the bottleneck is the shared hop (WiFi). If only the target is slow, the extra path (Ethernet/switch) is the issue.