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Commands using netstat

Terminal - Commands using netstat - 84 results

netstat -Aan | grep .80 | grep -v 127.0.0.1 | grep EST | awk '{print $6}' | cut -d "." -f1,2,3,4 | sort | uniq

2012-02-03 13:54:11

User: janvanderwijk

Functions: awk cut grep netstat sort

Tags: sort uniq grep netstat cut aix

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See who are using a specific port

See who is using a specific port. Especially when you're using AIX. In Ubuntu, for example, this can easily be seen with the netstat command.

netstat -tan | awk '$1 == "tcp" && $4 ~ /:/ { port=$4; sub(/^[^:]+:/, "", port); used[int(port)] = 1; } END { for (p = 32768; p <= 61000; ++p) if (! (p in used)) { print p; exit(0); }; exit(1); }'

2012-01-26 20:42:56

User: wirawan0

Functions: awk netstat

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find an unused unprivileged TCP port

This is also perl-less, and only uses AWK as its postprocessor. Tested with GAWK and MAWK.

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

netstat -a --numeric-ports | grep 8321

2012-01-20 22:00:56

User: peter4512

Functions: grep netstat

Tags: net tcp

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tell if a port is in use

if you don't do --numeric-ports, netstat will try to resolve them to names

netstat -plantu

This is sample output - yours may be different.

[root@server ~]# netstat -plantu
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program name
tcp        0      0 127.0.0.1:5901              0.0.0.0:*                   LISTEN      13696/Xvnc
tcp        0      0 0.0.0.0:111                 0.0.0.0:*                   LISTEN      2161/rpcbind
tcp        0      0 0.0.0.0:56144               0.0.0.0:*                   LISTEN      2350/rpc.statd
tcp        0      0 0.0.0.0:6001                0.0.0.0:*                   LISTEN      13696/Xvnc
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      2584/sshd
tcp        0      0 127.0.0.1:631               0.0.0.0:*                   LISTEN      2461/cupsd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      2678/master
tcp        0      0 0.0.0.0:5672                0.0.0.0:*                   LISTEN      2733/qpidd
tcp        0     52 172.16.21.10:22             172.16.16.133:2977          ESTABLISHED 13889/sshd
udp        0      0 0.0.0.0:50341               0.0.0.0:*                               2332/avahi-daemon
udp        0      0 0.0.0.0:830                 0.0.0.0:*                               2350/rpc.statd
udp        0      0 0.0.0.0:33476               0.0.0.0:*                               2350/rpc.statd
udp        0      0 0.0.0.0:5353                0.0.0.0:*                               2332/avahi-daemon
udp        0      0 0.0.0.0:750                 0.0.0.0:*                               2080/portreserve
udp        0      0 0.0.0.0:111                 0.0.0.0:*                               2161/rpcbind
udp        0      0 0.0.0.0:631                 0.0.0.0:*                               2461/cupsd
udp        0      0 0.0.0.0:634                 0.0.0.0:*                               2161/rpcbind

2012-01-19 00:18:43

User: player27

Functions: netstat

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Show all listening and established ports TCP and UDP together with the PID of the associated process

Easy to remenber. Fot TCP only use: netstat -plant

netstat -anpe

2011-12-06 18:27:09

User: anarcat

Functions: netstat

Tags: Network status diagnostic

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Lists all listening ports together with the PID of the associated process

Lists all opened sockets (not only listeners), no DNS resolution (so it's fast), the process id and the user holding the socket.

Previous samples were limiting to TCP too, this also lists UDP listeners.

netstat -atn | grep :22 | grep ESTABLISHED | awk '{print $4}' | sed 's/:22//'

2011-11-09 10:51:55

User: agambier

Functions: awk grep netstat sed

-1

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list current ssh clients

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netstat -plntu

2011-10-01 12:16:38

User: bolthorn0

Functions: netstat

Tags: netstat lsof networking

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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

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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)

while true ; do sleep 1 ; clear ; (netstat -tn | grep -P ':36089\s+\d') ; done

2011-09-28 11:39:43

User: hute37

Functions: clear grep netstat sleep true

-3

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Monitoring a port connections

shell loop to scan netstat output avoiding loolback aliases (local/remote swap for local connections)

netstat -rn | convert label:@- netstat.png

2011-09-21 11:52:28

User: appanax

Functions: netstat

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Command results as an image capture

We use the "convert" command (ImageMagick package) : see man convert (http://www.ma.utexas.edu/cgi-bin/man-cgi?convert+1)

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

netstat -tn | awk 'NR>2 {print $6}' | sort | uniq -c | sort -rn

2011-09-12 23:29:39

User: evandrix

Functions: awk netstat sort uniq

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Quick network status of machine

credit to tumblr engineering blog @ http://engineering.tumblr.com/

2011-09-08 18:54:36

User: brando56894

Functions: echo grep head netstat sudo tail

Tags: netstat udp tcp connections

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Displays All TCP and UDP Connections

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netstat -an |grep ":80" |awk '{print $5}' | sed s/::ffff://g | cut -d: -f1 |sort |uniq -c |sort -n | tail -1000 | grep -v "0.0.0.0"

2011-07-28 09:36:08

User: zeros

Functions: awk cut grep netstat sed sort tail uniq

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Find all IP connected to my host through TCP connection and count it

Count and Find all IP connected to my host through TCP connection.

netstat -nut | sed '/ESTABLISHED/!d;s/.*[\t ]\+$.*$:.*/\1/' | sort -u

2011-07-27 07:25:25

User: bitbasher

Functions: netstat sed sort

-1

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All IP connected to my host

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netstat -nut | awk '$NF=="ESTABLISHED" {print $5}' | cut -d: -f1 | sort -u

2011-07-27 07:24:10

User: bitbasher

Functions: awk cut netstat sort

-1

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All IP connected to my host

find all computer connected to my host through TCP connection

netstat -lantp | grep ESTABLISHED |awk '{print $5}' | awk -F: '{print $1}' | sort -u

2011-07-21 21:23:10

User: bitbasher

Functions: awk grep netstat sort

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All IP connected to my host

find all computer connected to my host through TCP connection.

netstat -nt | awk -F":" '{print $2}' | sort | uniq -c

2011-07-05 07:53:29

User: sreimann

Functions: awk netstat sort uniq

Tags: sort awk uniq netstat

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netstat with group by (ip adress)

count connections, group by IP and port

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netstat -ntu | awk ' $5 ~ /^[0-9]/ {print $5}' | cut -d: -f1 | sort | uniq -c | sort -n

2011-07-04 20:23:21

User: letterj

Functions: awk cut netstat sort uniq

Tags: netstat

-2

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netstat with group by (ip adress)

netstat has two lines of headers:

Active Internet connections (w/o servers)

Proto Recv-Q Send-Q Local Address Foreign Address State

Added a filter in the awk command to remove them

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netstat -ntu | awk ' $5 ~ /^[0-9]/ {print $5}' | cut -d: -f1 | sort | uniq -c | sort -n

2011-07-01 11:17:38

User: Koobiac

Functions: awk cut netstat sort uniq

Tags: netstat

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netstat with group by (ip adress)

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

netstat -nt | awk '{print $6}' | sort | uniq -c | sort -n -k 1 -r

2011-06-21 16:27:19

User: dennisfaust

Functions: awk netstat sort uniq

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Summarize the number of open TCP connections by state

Useful for checking the number and state of TCP connections.

netstat -n -f inet|awk '/\.389/{print $2}'|cut -f1-4 -d.|sort -u

2011-06-20 14:24:05

User: guptavi

Functions: awk cut netstat sort

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To find the LDAP clients connected to LDAP service running on Solaris

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watch -n 2 netstat -antu

2011-06-02 23:27:33

User: wilbercarmona

Functions: netstat watch

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Watch netstat output every 2 seconds

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netstat -ntu | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n

2011-05-25 20:53:34

User: unixmonkey21979

Functions: awk cut netstat sort uniq

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get the IP connected to the server (usefull to detect IP that should be blocked)

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netstat -lnptu

2011-05-19 21:16:35

User: mariusbutuc

Functions: netstat

Up
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Active Internet connections (only servers)

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while sleep 1; do date; (netstat -a -n | grep 80) ; done

2011-05-16 07:56:56

User: hute37

Functions: grep netstat sleep

Tags: netstat logging

-4

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Polls fos network port usage

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1 2 3 > Last ›