Commands tagged icmp (7)

  • send echo to socket network

    this command will send a message to the socket 25 on host 192.168.1.2 in tcp. works on udp and icmp understand only IP address, not hostname. on the other side (192.168.1.2), you can listen to this socket and test if you receive the message. easy to diagnose a firewall problem or not.


    25
    echo "foo" > /dev/tcp/192.168.1.2/25
    mobidyc · 2009-09-12 16:48:05 31
  • Disable the ping response

    It really disables all ICMP responses not only the ping one. If you want to enable it you can use: sudo -s "echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all"


    6
    sudo -s "echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_all"
    sliceoflinux · 2010-06-22 19:16:43 16
  • send echo to socket network

    Using netcat, usuallly installed on debian/ubuntu. Also to test against a sample server the following two commands may help echo got milk? | netcat -l -p 25 python -c "import SocketServer; SocketServer.BaseRequestHandler.handle = lambda self: self.request.send('got milk?\n'); SocketServer.TCPServer(('0.0.0.0', 25), SocketServer.BaseRequestHandler).serve_forever()" Show Sample Output


    2
    echo foo | netcat 192.168.1.2 25
    pykler · 2009-09-13 01:33:02 4
  • Nmap find open TCP/IP ports for a target that is blocking ping

    Change the IP address from 127.0.0.1 to the target machines ip address. Even if the target has ICMP (ping) blocked, it will show you what ports are open on the target. Very handy for situations where you know the target is up and online but wont respond to pings. Show Sample Output


    0
    nmap -sT -PN -vv <target ip>
    Richie086 · 2011-07-22 02:37:19 9
  • OneLiner ICMP sniffer in Python

    Quick OneLiner to sniff for ICMP traffic, proof of concept socket code. Needs root privs to run. Show Sample Output


    0
    echo "exec(\"import socket, os\nwhile True:\n\tprint (socket.socket(socket.AF_INET, socket.SOCK_RAW, socket.IPPROTO_ICMP)).recvfrom(65565)\")" | sudo python
    justinf · 2015-05-24 08:19:55 13
  • Powershell Ping Logs Host Up/Down Events

    IMPORTANT: You need Windows PowerShell to run this command - in your Windows Command Prompt, type powershell Uses sajb to start a PowerShell background job that pings an IP host every 10 seconds. Any changes in the host's Up/Down state is time-stamped and logged to a file. Date/time stamps are logged in two formats: Unix and human-readable. A while(1) loop repeats the test every 10 seconds by using the sleep command. See the Sample Output for more detail. I use this command to log Up/Down events of my Motorola SB6141 cable modem (192.168.100.1). To end the logging, close the PowerShell window or use the "exit" command. Show Sample Output


    0
    sajb {$ip="192.168.100.1";$old=0;while(1){$up=test-connection -quiet -count 1 $ip;if($up-ne$old){$s=(date -u %s).split('.')[0]+' '+(date -f s).replace('T',' ')+' '+$ip+' '+$(if($up){'Up'}else{'Down'});echo $s|out-file -a $home\ping.txt;$old=$up}sleep 10}}
    omap7777 · 2015-12-28 20:33:08 15
  • send echo to socket network

    you can use a pair of commands to test firewalls. 1st launch this command at destination machine ncat -l [-u] [port] | cat then use this command at source machine to test remote port echo foo | ncat [-u] [ip address] [port] First command will listen at specified port. It will listen TCP. If you use -u option will listen UDP. Second command will send "foo" through ncat and will reach defined IP and port. Show Sample Output


    -1
    echo foo | ncat [ip address] [port]
    dragonauta · 2012-10-26 10:53:47 7

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

Share Your Commands

Check These Out

Batch convert PNG to JPEG
Convert all PNG images in directory to JPEG using ImageMagick, and delete the old PNG images.

Remove all unused kernels with apt-get
This will remove all installed kernels on your debian based install, except the one you're currently using. From: http://tuxtweaks.com/2009/12/remove-old-kernels-in-ubuntu/comment-page-1/#comment-1590

Takes and displays screenshot of Android phone over adb.
Dependencies on phone: adb access, screencap command, base64 command. Dependencies on computer: adb, sed, base64, display (from imagemagick, but can substitute other image viewer which reads from stdin). This should work around adb stupidies (i.e. that it replaces \n with \r\n) with base64.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Rename files in batch

Read aloud a text file in Mac OS X

list ips with high number of connections

Better git diff, word delimited and colorized
I've been using colordiff for years. wdiff is the new fav, except its colors. Word delimited diffs are more interleaved, easing the chore of associating big blocks of changes.

Pipe stdout and stderr, etc., to separate commands
You can use [n]> combined with >(cmd) to attach the various output file descriptors to be the input of different commands.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Stay in the loop…

Follow the Tweets.

Every new command is wrapped in a tweet and posted to Twitter. Following the stream is a great way of staying abreast of the latest commands. For the more discerning, there are Twitter accounts for commands that get a minimum of 3 and 10 votes - that way only the great commands get tweeted.

» http://twitter.com/commandlinefu
» http://twitter.com/commandlinefu3
» http://twitter.com/commandlinefu10

Subscribe to the feeds.

Use your favourite RSS aggregator to stay in touch with the latest commands. There are feeds mirroring the 3 Twitter streams as well as for virtually every other subset (users, tags, functions,…):

Subscribe to the feed for: