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Commands tagged networking

Terminal - Commands tagged networking - 23 results

watch "lsof -i -P |grep ESTABLISHED |awk '{printf \"%15.15s \\t%s\\n\", \$1, \$9}'"

2013-04-03 02:04:11

User: skarfacegc

Functions: watch

Tags: lsof watch networking awk grep

Up
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What addresses are your applications talking to?

Shows which applications are making connections, and the addresses they're connecting to. Refreshes every 2 seconds (watch's default). Test on OSX, should work anywhere watch and lsof work.

nc -l <port-number>

2013-03-20 15:25:57

User: cybertoast

Tags: networking firewall socket port listen

-1

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Listen on an arbitrary port

Simple way to test if a port is available to the public. Run this command on the "server" and run a `telnet host-ip port-number` on the client. Test by sending strings to the server, which will be displayed in the server terminal.

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

/sbin/ifenslave -c bond0 eth1

2013-02-06 16:04:35

User: tduvally

Tags: Linux networking bonding

Up
Down

Change active bond slave

This forces a bonded interface to switch to another slave in the bond as its active slave.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

telnet 0 <port>

2012-11-16 03:38:49

User: somaddict

Functions: telnet

Tags: Network ssh bash ping shell shortcut telnet var networking speed loopback

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Test against loopback address with the 0.0.0.0 default route.

Super fast way to ftp/telnet/netcat/ssh/ping your loopback address for testing. The default route 0.0.0.0 is simply reduced to 0.

ifconfig eth0 allmulti

2012-05-25 16:43:41

User: SEJeff

Functions: ifconfig

Tags: Linux networking crimsonfu multicast

Up
Down

Disable an interface's multicast filter for testing

Disabling an interface's multicast filter is like disabling IGMP snooping on a switch. It is useful for testing and troubleshooting.

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

tcpdump -w - |pv -bert >/dev/null

2011-12-14 00:24:02

User: h3xx

Functions: tcpdump

Tags: tcpdump pv network performance networking

Up
Down

Show network throughput

Real gurus don't need fancy tools like iftop or jnettop.

nmap -v -sT 192.168.0.0/24

2011-11-19 07:06:52

User: Dhinesh

Tags: nmap networking

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Down

nmap port scanning

TCP Connect scanning for localhost and network 192.168.0.0/24

lsof -Pi | grep LISTEN

2011-10-03 12:50:18

User: 5partan

Functions: grep

Tags: lsof networking

-2

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check open ports (both ipv4 and ipv6)

This option is much faster, as it checks only network nodes.

lsof -i

2011-10-03 02:06:30

User: shsingh

Tags: lsof networking

-1

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check open ports (both ipv4 and ipv6)

This option selects the listing of all Internet and x.25 (HP-UX) network files.

netstat -plntu

2011-10-01 12:16:38

User: bolthorn0

Functions: netstat

Tags: netstat lsof networking

Up
Down

check open ports (both ipv4 and ipv6)

Check open TCP and UDP ports

netstat -plnt

2011-09-30 19:56:32

User: DopeGhoti

Functions: netstat

Tags: netstat lsof networking

Up
Down

check open ports (both ipv4 and ipv6)

While `lsof` will work, why not use the tool designed explicitly for this job?

(If not run as root, you will only see the names of PID you own)

lsof -Pn | grep LISTEN

2011-09-29 18:21:51

User: pykler

Functions: grep

Tags: lsof networking

Up
Down

check open ports (both ipv4 and ipv6)

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

netstat -tulpnc

This is sample output - yours may be different.

tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      -
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6010          0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6011          0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6012          0.0.0.0:*               LISTEN      -
tcp        0      0 :::111                  :::*                    LISTEN      -
tcp        0      0 :::5556                 :::*                    LISTEN      20921/java
tcp        0      0 :::22                   :::*                    LISTEN      -
tcp        0      0 ::1:631                 :::*                    LISTEN      -
tcp        0      0 127.0.0.2:7001          :::*                    LISTEN      20842/java
tcp        0      0 127.0.0.1:7001          :::*                    LISTEN      20842/java
tcp        0      0 10.249.135.171:7001     :::*                    LISTEN      20842/java
tcp        0      0 ::1:7001                :::*                    LISTEN      20842/java
tcp        0      0 fe80::7a2b:cbff:fe:7001 :::*                    LISTEN      20842/java
tcp        0      0 ::1:25                  :::*                    LISTEN      -
tcp        0      0 ::1:6010                :::*                    LISTEN      -
tcp        0      0 ::1:6011                :::*                    LISTEN      -
tcp        0      0 ::1:6012                :::*                    LISTEN      -
udp        0      0 0.0.0.0:111             0.0.0.0:*                           -
udp        0      0 0.0.0.0:631             0.0.0.0:*                           -
udp        0      0 0.0.0.0:670             0.0.0.0:*                           -
udp        0      0 0.0.0.0:26791           0.0.0.0:*                           -
udp        0      0 0.0.0.0:5353            0.0.0.0:*                           -
udp        0      0 0.0.0.0:39640           0.0.0.0:*                           -
udp        0      0 :::111                  :::*                                -
udp        0      0 :::546                  :::*                                -
udp        0      0 :::670                  :::*                                -
udp        0      0 :::43339                :::*                                -
(Not all processes could be identified, non-owned process info
 will not be shown, you would have to be root to see it all.)
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
tcp        0      0 0.0.0.0:111             0.0.0.0:*               LISTEN      -
tcp        0      0 0.0.0.0:22              0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:631           0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:25            0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6010          0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6011          0.0.0.0:*               LISTEN      -
tcp        0      0 127.0.0.1:6012          0.0.0.0:*               LISTEN      -
tcp        0      0 :::111                  :::*                    LISTEN      -
tcp        0      0 :::5556                 :::*                    LISTEN      20921/java
tcp        0      0 :::22                   :::*                    LISTEN      -
tcp        0      0 ::1:631                 :::*                    LISTEN      -
tcp        0      0 127.0.0.2:7001          :::*                    LISTEN      20842/java
tcp        0      0 127.0.0.1:7001          :::*                    LISTEN      20842/java
tcp        0      0 10.249.135.171:7001     :::*                    LISTEN      20842/java
tcp        0      0 ::1:7001                :::*                    LISTEN      20842/java
tcp        0      0 fe80::7a2b:cbff:fe:7001 :::*                    LISTEN      20842/java
tcp        0      0 ::1:25                  :::*                    LISTEN      -
tcp        0      0 ::1:6010                :::*                    LISTEN      -
tcp        0      0 ::1:6011                :::*                    LISTEN      -
tcp        0      0 ::1:6012                :::*                    LISTEN      -
udp        0      0 0.0.0.0:111             0.0.0.0:*                           -
udp        0      0 0.0.0.0:631             0.0.0.0:*                           -
udp        0      0 0.0.0.0:670             0.0.0.0:*                           -
udp        0      0 0.0.0.0:26791           0.0.0.0:*                           -
udp        0      0 0.0.0.0:5353            0.0.0.0:*                           -
udp        0      0 0.0.0.0:39640           0.0.0.0:*                           -
udp        0      0 :::111                  :::*                                -
udp        0      0 :::546                  :::*                                -
udp        0      0 :::670                  :::*                                -
udp        0      0 :::43339                :::*                                -

2011-04-20 07:30:31

User: altern

Functions: netstat

Tags: networking port

Up
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showing opened ports on machine

shows opened ports on machine in continuous mode (refreshing every 10 sec)

curl -s http://standards.ieee.org/regauth/oui/oui.txt | grep $1

2010-04-29 23:52:01

User: prayer

Functions: grep

Tags: networking

Up
Down

online MAC address lookup

Comments (2) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

ping -I eth0 www.yahoo.com

2010-04-12 06:25:07

User: octopus

Functions: ping

Tags: ping networking

Up
Down

How to check network connection from one interface

This command only check the network connection from given eth. This is very useful if you are using more then one interface in your server or laptop.

python -c "import platform; print platform.node()"

2010-03-24 09:09:34

User: keimlink

Functions: python

Tags: hostname python networking

-3

Up
Down

Print your local hostname with python

tcpdump -i any -n tcp[13] == 2

2010-01-21 14:18:16

User: wincus

Functions: tcpdump

Tags: tcpdump networking

Up
Down

show tcp syn packets on all network interfaces

Comments (0) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

iptraf

2009-12-30 15:41:21

User: linuxrawkstar

Tags: network performance networking iptraf

Up
Down

monitor network traffic and throughput in real time

see http://iptraf.seul.org/ for all kinds of documentation and screenshots

Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate

ifconfig eth1 | grep inet\ addr | awk '{print $2}' | cut -d: -f2 | sed s/^/eth1:\ /g

2009-11-03 19:26:40

User: TuxOtaku

Functions: awk cut grep ifconfig sed

Tags: ifconfig sed awk grep cut regex networking

Up
Down

Grab an interface's IP from ifconfig without screen clutter

Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.

python -c 'import socket; s = socket.socket(socket.AF_INET, socket.SOCK_STREAM); s.connect(("<hostname>", <port>)); print s.getsockname()[0] ; s.close() ;' 2> /dev/null

2009-10-13 16:21:15

User: angleto

Functions: python

Tags: python networking tcp socket

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retrieve the source address used to contact a given host

on multihomed hosts, connected to several networks, could be usefull to know the source address (local ip address) used to reach the target host, this command does not require root priviledges.

The command use a TCP socket, if there is any error the command return an empty string, elsewhere return a valid ip address.

netstat -ltun

2009-10-05 08:39:03

User: Decoy

Functions: netstat

Tags: Linux netstat networking

Up
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List open TCP/UDP ports

Works only on Linux.

Last option (n) turn name of service resolving (/etc/services) off.

ethtool eth0

2009-08-28 04:22:03

User: unixbhaskar

Tags: commandlinefu networking

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Down

Get ethernet card information.

This is an commandline utility to get fair piece of information about the attached network card.

while true; do clear; nmap ${hostname} -PN -p ${hostport}; sleep 5; done

2009-08-14 20:19:59

User: flokra

Functions: sleep

Tags: nmap networking

Up
Down

checks if host /service is up on a host that doesn't respond to ping

the command for the impatient sysadmin: simply checks every five secs, if a host or a specific service running on it is up. ideal for hosts that are configured not to respond on pings.