Print human-friendly timestamps and inter-packet deltas with tcpdump, and see exact examples to reproduce. 25.12.2025 | reading time: 2 min Want to know not only which packet arrived but exactly when? Use tcpdump's timestamp options to print human-friendly dates, epoch seconds or inter-packet deltas so troubleshooting and latency measurements become obvious. Quick hands-on capture Run this on a host with traffic and watch the timestamps: ```shell tcpdump -i eth0 -nn -tttt -c 3 port 80 2025-12-25 12:34:56.789012 IP 192.168.1.10.54321 > 93.184.216.34.80: Flags [P.], seq 1:518, ack 1, win 229, length 517 2025-12-25 12:34:58.012345 IP 93.184.216.34.80 > 192.168.1.10.54321: Flags [.], ack 518, win 502, length 0 2025-12-25 12:35:00.123456 IP 192.168.1.10.54321 > 93.184.216.34.80: Flags [F.], seq 518, ack 502, win 229, length 0 ``` What each flag does Try these and learn by doing: `-tttt` prints full date and time for each packet, `-ttt` prints the delta since the previous packet, `-tt` prints raw seconds since the epoch, and `-t` suppresses timestamps entirely; combine with `-nn` to keep numeric addresses and `-s 0` to capture full packet payloads. Common workflows Measure response times with `-ttt`, correlate logs by using `-tttt` when reading saves (`-w` and `-r`), and script comparisons by saving pcaps then replaying or analyzing timestamps with `tcpdump -tttt -r file.pcap` so the exact packet timing is preserved. Where tcpdump fits For quick, line-oriented inspection tcpdump is ideal; when a GUI or protocol dissection is needed open the pcap in Wireshark, and when automation or extraction is required use tshark or filters to pull the timestamp fields into scripts. Next steps Practice captures on noisy and quiet interfaces, compare `-tt`, `-ttt` and `-tttt` outputs, then move on to reading pcap files and correlating with system logs; deepen skills and consider formal certification such as CompTIA Linux+ or LPIC-1 with intensive exam prep at bitsandbytes.academy. Join Bits & Bytes Academy First class LINUX exam preparation. network utilities troubleshooting
