User Tools

Site Tools


Sidebar






newpage

linux:network

Networking

useful programs

tcpdump

Tcpdump prints out a description of the contents of packets on a network interface that match the boolean expression..

Examples:

  • dns: $ tcpdump -i eth0 'udp port 53'
  • http: $ tcpdump 'tcp port 80'
  • ftp: $ tcpdump -i eth0 '(port 21 or 20)'

mtr - mytraceroute

mtmtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool.r combines the functionality of the traceroute and ping programs in a single network diagnostic tool.

iptraf

iptraf is an ncurses-based IP LAN monitor GUI that generates various network statistics including TCP info, UDP counts, ICMP and OSPF information, Ethernet load info, node stats, IP checksum errors, and others…

iftop

iftop listens to network traffic on a named interface … and displays a table of current bandwidth usage by pairs of hosts.

-i interface

-p Run in promiscuous mode

-P Turn on port display

-F net/mask – Specifies a network for traffic analysis

iperf

Measures the bandwith of a connections

iperf -c iperf.ovh.net -m -i 1 -t 10 -r

It's usefull to check LAN Cables: Connect two computers with the cable, setup static IP Addresses and start iperf on both:

Server mode on 1. box:

iperf -s   

Client mode on 2. box:

iperf -c <IP Address of box 1>

In the results you get the Banwidth:

[  4] local <IP Addr node2> port 5001 connected with <IP Addr node1> port 2357
[ ID] Interval       Transfer     **Bandwidth**
[  4]  0.0-10.1 sec   6.5 MBytes   **305.2 Mbits/sec**
linux/network.txt · Last modified: 2021/03/11 02:20 by tkilla