netstat -tlpn | sort -t: -k2 -n

List Listen Port by numbers

Show TCP Listen ports sorted by number (bugs: IPV6 addresses not supported)
Sample Output
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0 *                   LISTEN      453/java            
tcp        0      0      *                   LISTEN      1410/postmaster     
tcp        0      0    *                   LISTEN      1023/postmaster     
tcp        0      0      *                   LISTEN      6118/Xvnc           

By: hute37
2014-07-22 14:08:01

These Might Interest You

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    echo foo | ncat [ip address] [port]
    dragonauta · 2012-10-26 10:53:47 0
  • swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

    lsof -iTCP:80 -sTCP:LISTEN
    indexsmithy · 2018-04-07 16:20:25 0

  • 2
    netstat -ntlp | grep -w 80 | awk '{print $7}' | cut -d/ -f1
    ncaio · 2009-05-20 20:29:56 4
  • Doesn't list connections to other ports than port 80. Not f.e. 8080 or 8091. Excludes programs listening for connections, like your favorite webserver.

    watch "netstat -plan | grep -v LISTEN | grep \":80 \" | awk {'print \$5'} | cut -d: -f 1 | uniq -c | sort -nk 1"
    simonsimcity · 2013-09-05 13:50:00 0
  • 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.

    nc -l <port-number>
    cybertoast · 2013-03-20 15:25:57 1
  • "sort_csn" is a function to sort a comma separated list of numbers. Define the the function with this: sort_csn () { echo "${1}" | sed -e "s/,/\n/g"| sort -nu | awk '{printf("%s,",$0)} END {printf("\n")}' | sed -e "s/,$//"; } Use the function like this: sort_csn 443,22,80,8200,1533,21,1723,1352,25 21,22,25,80,443,1352,1533,1723,8200 One example where this is useful is when port scanning with nmap and getting a list of open ports in random order. If you use Nessus, you may need to create a scan policy for that set of specific ports and it is clearer to read with the port numbers in ascending order (left to right). Caveat: no spaces in the comma separated list (just number1,number2,number3,etc). A variation of this to sort a comma separated list of strings: sort_css () { echo "${1}" | sed -e "s/,/\n/g"| sort -u | awk '{printf("%s,",$0)} END {printf("\n")}' | sed -e "s/,$//"; } usage: sort_css apples,pears,grapes,melons,oranges apples,grapes,melons,oranges,pears Show Sample Output

    sort_csn () { echo "${1}" | sed -e "s/,/\n/g"| sort -nu | awk '{printf("%s,",$0)} END {printf("\n")}' | sed -e "s/,$//"; }
    mpb · 2011-01-26 15:18:08 2

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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