Commands using watch (155)

  • Monitor incoming connections of proxies and balancers.

    Maybe this will help you to monitor your load balancers or reverse proxies if you happen to use them. This is useful to discover TIME OUTS and this will let you know if one or more of your application servers is not connected by checking. Show Sample Output


    2
    watch -n 1 "/usr/sbin/lsof -p PID |awk '/TCP/{split(\$8,A,\":\"); split(A[2],B,\">\") ; split(B[1],C,\"-\"); print A[1],C[1],B[2], \$9}' | sort | uniq -c"
    ideivid · 2011-08-12 19:16:38 3
  • Server load and process monitoring

    In certain cases you mighy need to monitor the server load caused by certain process. For example HTTP, while stress testing apache using ab (apache benchmark) you may want to monitor the server status,load, # of spawned HTTP processes, # of established connections, # of connections in close wait state, apache memory footprint etc. Show Sample Output


    2
    watch -n1 "uptime && ps auxw|grep http|grep -v grep | grep -v watch|wc -l && netstat -ntup|grep :80 |grep ESTABLISHED|wc -l && netstat -ntup|grep :80|grep WAIT|wc -l && free -mo && ps -ylC httpd --sort:rss|tail -3|awk '{print \$8}'"
    rockon · 2012-06-06 12:12:10 5
  • Watch active calls on an Asterisk PBX

    This handles when you have a single call or channel. Other commands will strip out the result if there is a single channel or call active because the output changes the noun to be singular instead of plural. Show Sample Output


    2
    watch "asterisk -vvvvvrx 'core show channels' | egrep \"(call|channel)\""
    rowshi · 2012-08-29 13:40:45 5
  • send DD a signal to print its progress

    Sends the "USR1" signal every 1 second (-n 1) to a process called exactly "dd". The signal in some systems can be INFO or SIGINFO ... look at the signals list in: man kill


    2
    watch -n 1 pkill -USR1 "^dd$"
    ivanalejandro0 · 2012-08-31 05:15:45 4
  • Monitor memory fine-grained usage (e.g. firefox)

    Sometimes top/htop don't give the fine-grained detail on memory usage you might need. Sum up the exact memory types you want


    2
    watch "awk '/Rss/{sum += \$2; } END{print sum, \"kB\"}' < /proc/$(pidof firefox)/smaps"
    gumnos · 2015-09-19 00:36:34 18
  • Monitor cpu in realtime.


    2
    watch grep \"cpu MHz\" /proc/cpuinfo
    wuseman1 · 2018-11-11 00:45:28 474
  • Watch how many tcp connections there are per state every two seconds.


    2
    $ watch -c "netstat -natp 2>/dev/null | tail -n +3 | awk '{print \$6}' | sort | uniq -c"
    emanuele · 2018-11-22 10:37:48 333
  • Watch TCP, UDP open ports in real time with socket summary.


    2
    watch ss -stplu
    wuseman1 · 2019-07-16 20:41:36 43
  • Test http request every second, fancy display.

    Use the command watch, which is really hard to pass nested quotes to, and insert newlines where they are supposed to go in the HTTP request. that is after 1.1 after the host and two newlines at the end before the EOF. i use this all day what? no support for HEREDOCs on commandlinefu's interface? need more fu. Show Sample Output


    1
    watch -n 1 nc localhost 80 '<<EOF GET / HTTP/1.1 Host: tux-ninja Connection: Close EOF'
    JustinHop · 2009-08-06 23:20:31 4
  • Not a kismet replacement...

    If you're like some individuals who rely on ndiswrapper and cannot use kismet, this command may be of service. watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption'" Or... watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption' | egrep 'linksys'" :-) Hopefully you'll find some dd-wrt compatible routers.


    1
    watch -n .5 "iwlist wlan0 scan"
    Abiden · 2009-08-20 23:05:04 3
  • Watching Command

    If you need to keep an eye on a command whose output is changing, use the watch command. For example, to keep an eye on your load average


    1
    watch 'cat /proc/loadavg'
    0disse0 · 2009-09-03 20:10:46 4
  • Battery real life energy vs predicted remaining plotted

    This time I added a print to reemaining energy, every minute, time stamped. The example shown here is complete and point to large discrepancies as time passes, converging to accuracy near the end. Show Sample Output


    1
    echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
    m33600 · 2009-10-19 05:28:15 4
  • Monitor a file's size


    1
    watch -n 60 du /var/log/messages
    rbossy · 2009-10-27 14:53:41 3
  • watch the previous command

    If you just executed some long command, like "ps -aefww | grep -i [m]yProcess", and if you don't want to retype it or cycle backwards in history and waste time quoting it, then you can use history substitution.


    1
    watch -n1 -d !!
    TeacherTiger · 2009-11-24 21:01:14 3
  • Monitoring sessions that arrive at your server


    1
    watch -n 1 -d "finger"
    tsiqueira · 2009-12-08 14:53:18 3
  • watch snapshots commit in VMware ESX

    To monitor .vmdk files during snapshot deletion (commit) on ESX only (ESXi doesn't have the watch command): 1. Navigate to the VM directory containing .vmdk files. # watch "ls -tough --full-time *.vmdk" where: -t sorts by modification time -o do not list group information (to narrow the output) -u sorts by access time -g only here for the purpose to easily remember the created mnemonic word 'tough' -h prints sizes in human readable format (e.g., 1K 234M 2G) --full-time sets the time style to full-iso and does not list user information (to narrow the output) optionally useful parameters to the watch command: -d highlight changes between updates -n seconds to wait between updates (default is 2) -t turn off printing the header


    1
    watch 'ls -tough --full-time *.vmdk'
    vRobM · 2010-08-20 17:28:28 6
  • Remind yourself every 15 minutes (repeated reminders)

    Note: 1) -n option of watch accepts seconds 2) -t option of notify-send accepts milliseconds 3) All quotes stated in the given example are required if notification message is more than a word. 4) I couldn't get this to run in background (use of & at the end fails). Any suggestions/improvements welcome.


    1
    watch -n 900 "notify-send -t 10000 'Look away. Rest your eyes'"
    b_t · 2010-10-05 09:39:31 6
  • Watch and cat the last file to enter a directory

    Great for watching things like Maildir's or any other queue directory.


    1
    watch "cat `ls -rcA1 | tail -n1`"
    donnoman · 2011-03-25 01:22:05 8
  • monitor the last command run


    1
    watch !!
    wincus · 2011-07-05 12:50:56 7
  • Watch the disk fill up with change highlighting

    If you add the -d flag each difference in the command's output will be highlighted. I also monitor individual drives by adding them to df. Makes for a nice thin status line that I can shove to the bottom of the monitor.


    1
    watch -d -n 5 df
    pcphillips · 2011-08-24 19:45:36 6
  • Monitor connection statistics with netstat and watch


    1
    watch -n 1 "netstat -ntu | sed '1,2d' | awk '{ print \$6 }' | sort | uniq -c | sort -k 2"
    facecool · 2011-09-30 09:04:14 3
  • UPS Tracking Script


    1
    watch -t -c -n30 'wget -q -O- "http://wwwapps.ups.com/WebTracking/processInputRequest?TypeOfInquiryNumber=T&InquiryNumber1=1Z4WYXXXXXXXXXX" | html2text | sed -n "/Shipment Progress/,/Shipping Information/p" | grep -v "*" | ccze -A'
    mfr · 2013-06-20 06:01:25 15
  • A bash timer

    Starts and shows a timer. banner command is a part of the sysvbanner package. Instead of the banner an echo or figlet commands could be used. Stop the timer with Ctrl-C and elapsed time will be shown as the result. Show Sample Output


    1
    alias timer='export ts=$(date +%s);p='\''$(date -u -d @"$(($(date +%s)-$ts))" +"%H.%M.%S")'\'';watch -n 1 -t banner $p;eval "echo $p"'
    ichbins · 2013-08-24 16:18:45 13
  • Like top but for files

    Like top, but for files


    1
    watch -d -n 2 'df; ls -FlAt;'
    G2G · 2013-09-17 05:44:47 6
  • Watch a dig in progress

    Watch a dig in progress Show Sample Output


    1
    watch -n1 dig google.com
    ene2002 · 2013-12-26 19:23:27 13
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Disassemble all ACPI tables on your system
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Search for a word in less
Although less behaves more or less like vim in certain aspects, the vim regex for word boundaries (\< and \>) do not work in less. Instead, use \b to denote a word boundary. Therefore, if you want to search for, say, the word "exit", but do not want to search for exiting, exits, etc., then surround "exit" with \b. This is useful if you need to search for specific occurrences of a keyword or command. \b can also be used at just the beginning and end, if needed.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Display the human-readable sizes of all files and folders in the current directory with 3 decimal places
To sort the list by file/directory size, insert `sort -n |` before `awk`.

function to compute what percentage of X is Y? Where percent/100 = X/Y => percent=100*X/Y
This function make it easy to compute X/Y as a percentage. The name "wpoxiy" is an acronym of "what percentage of X is Y"

print the name of each package APT knows [matching a prefix]
In this case, linux- is the prefix; simply running $apt-cache pkgnames would list every package APT knows about. The default APT config assumes -g, --generate; to use the cache as/is, you could similarly run: $apt-cache --no-generate pkgnames [prefix] Adding --all-names, like so: $apt-cache --no-generate --all-names pkgnames [prefix] would print all the packages APT knows about, using the cache as/is, including virtual packages and missing dependencies. This command was shamelessly stolen from the apt-cache(8) man-page.

Greets the user appropriately

Securely destroy data on given device hugely faster than /dev/urandom
This command generates a pseudo-random data stream using aes-256-ctr with a seed set by /dev/urandom. Redirect to a block device for secure data scrambling.

Print the 10 deepest directory paths

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