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Commands using watch

Commands using watch from sorted by
Terminal - Commands using watch - 109 results
watch "netstat -plan|grep :80|awk {'print \$5'} | cut -d: -f 1 | sort | uniq -c | sort -nk 1"
2010-03-15 09:27:43
User: ik_5
Functions: watch
Tags: monitoring httpd port 80
17
Up
Down
Monitor open connections for httpd including listen, count and sort it per IP

It's not my code, but I found it useful to know how many open connections per request I have on a machine to debug connections without opening another http connection for it.

You can also decide to sort things out differently then the way it appears in here.

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watch -n 7 -d 'uptime | sed s/.*users?, //'
2010-01-17 18:45:52
User: matthewbauer
Functions: sed watch
-1
Up
Down
keep an eye on system load changes
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watch -n1 "du -hs /home/$USER | cut -f1 -d'/' | figlet -k"
2010-01-07 07:30:59
User: cviorel
Functions: watch
3
Up
Down
Watch the size of a directory using figlet

You can substitute /home/$USER with any path you like.

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watch 'dmesg | tail -15'
2009-12-20 02:00:05
User: Heoa
Functions: tail watch
-1
Up
Down
Monitor the Kernel Ring Buffer

Useful with new unknown devices or just monitoring, probably useful for the sysadmin. Updates every 2 seconds. More here: http://linuxclisecurity.blogspot.com/2009/12/monitor-kernel-ring-buffer.html.

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SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234 TARGET: netcat -l -p 1234 | dd of=/dev/mapper/laptop bs=16065b STATS on target: watch -n60 -- kill -USR1 $(pgrep dd)
2009-12-16 10:51:06
User: bw
Functions: dd kill watch
5
Up
Down
create disk copy over the net without temp files

I wanted to create a copy of my whole laptop disk on an lvm disk of the same size.

First I created the logical volume: lvcreate -L120G -nlaptop mylvms

SOURCE: dd if=/dev/sda bs=16065b | netcat ip-target 1234

TARGET: nc -l -p 1234 | dd of=/dev/mapper/mylvms-laptop bs=16065b

to follow its process you issue the following command in a different terminal

STATS: on target in a different terminal: watch -n60 -- kill -USR1 $(pgrep dd)

(see http://www.commandlinefu.com/commands/view/4356/output-stats-from-a-running-dd-command-to-see-its-progress)

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watch -n60 --kill -USR1 $(pgrep dd)
2009-12-16 10:35:28
User: bw
Functions: watch
2
Up
Down
output stats from a running dd command to see its progress

if you start a large dd and forgot about statistics, but you still wonder what the progress is this command in an OTHER terminal will show you the way.

NOTE: the watch command by itself will not output anything

NOTE: the kill command will not kill the process

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watch -d 'sudo smartctl -a /dev/sda | grep Load_Cycle_Count ; sudo smartctl -a /dev/sda | grep Temp'
2009-12-15 00:15:24
User: vxbinaca
Functions: grep sudo watch
2
Up
Down
Expedient hard disk temprature and load cycle stats

This command is a great way to check to see if acpi is doing damage to your disks by agressivly parking the read arm and wearing down it's life. As you can see, mine has lost half its life. I'm sure this could be shortened though somehow. It will use smartctl to dump the stats and then grep out just the temperature and load cycles for the disk (a load cycle is when a the read arm comes out of park and wears on the drive).

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watch -n 1 -d "finger"
2009-12-08 14:53:18
User: tsiqueira
Functions: watch
1
Up
Down
Monitoring sessions that arrive at your server
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watch vmstat -sSM
2009-12-04 22:35:45
User: servermanaged
Functions: vmstat watch
4
Up
Down
Monitor memory usage

Monitor with watch command and vmstat, memory usage

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watch -n 1 "ps aux | sed -n 's/ D /&/p'"
2009-12-03 18:22:44
User: lunarblu
Functions: watch
0
Up
Down
Watch those evil Red Hat states code D Uninterruptible sleep (usually IO).

On my cluster a D in the states column means it is time to reboot the server.

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watch -n1 -d !!
2009-11-24 21:01:14
User: TeacherTiger
Functions: watch
1
Up
Down
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.

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watch -n 10 killall -USR1 dd
2009-11-09 00:03:34
User: Clopnixus
Functions: killall watch
10
Up
Down
check the status of 'dd' in progress
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watch -n 1 'echo "obase=2;`date +%s`" | bc'
2009-11-04 02:04:00
User: matthewbauer
Functions: watch
Tags: binary clock binary clock
33
Up
Down
Binary Clock

Create a binary clock.

Show sample output | Comments (5) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
watch -n 60 du /var/log/messages
2009-10-27 14:53:41
User: rbossy
Functions: du watch
1
Up
Down
Monitor a file's size
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export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | toilet -f shadow'
2009-10-23 07:56:30
User: m33600
Functions: date echo export printf watch
0
Up
Down
StopWatch, toilet version, amazing format inside terminal

already described on the other two versions, this one uses ascii characters on game style to display elapsed time.

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export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds) | osd_cat -o 20 -d 1 -p bottom'
2009-10-23 07:47:11
User: m33600
Functions: date echo export printf watch
0
Up
Down
StopWatch, OnScreen version, blinking shily on all desktops

Variation of the theme, this one blinks in low profile on top level of X, ie, it is visible, indeed small.

Try changing fonts and sizes of osd_cat

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export I=$(date +%s); watch -t -n 1 'T=$(date +%s);E=$(($T-$I));hours=$((E / 3600)) ; seconds=$((E % 3600)) ; minutes=$((seconds / 60)) ; seconds=$((seconds % 60)) ; echo $(printf "%02d:%02d:%02d" $hours $minutes $seconds)'
2009-10-23 07:31:44
User: m33600
Functions: date echo export printf watch
3
Up
Down
StopWatch, simple text, hh:mm:ss using Unix Time

Works on real time clock, unix time based, decrementing the actual time from initial time saved in an environment variable exported to child process inside watch

Shows elapsed time from start of script in hh:mm:ss format

Non afected by system slow down due to the use of date.

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echo start > battery.txt; watch -n 60 'date >> battery.txt ; acpi -b >> battery.txt'
2009-10-19 05:28:15
User: m33600
Functions: acpi echo watch
1
Up
Down
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.

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echo start > battery.txt; watch -n 60 'date >> battery.txt'
2009-10-18 07:00:26
User: m33600
Functions: echo watch
0
Up
Down
Do you really believe on Battery Remaining Time? Confirm it from time to time!

Fully recharge your computer battery and start this script.

It will create or clean the file named battery.txt, print a start on it and every minute it will append a time stamp to it.

Batteries last few hours, and each hour will have 60 lines of time stamping. Really good for assuring the system was tested in real life with no surprises.

The last time stamp inside the battery.txt file is of interest. It is the time the computer went off, as the battery was dead!

Turn on your computer after that, on AC power of course, and open battery.txt. Read the first and last time stamps and now you really know if you can trust your computer sensors.

If you want a simple line of text inside the battery.txt file, use this:

watch -n 60 'date > battery.txt'

The time of death will be printed inside

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watch -n60 du /var/log/messages
2009-10-09 18:37:45
User: matrixguy
Functions: du watch
8
Up
Down
Monitor a file's size

use "watch" instead of while-loops in these simple cases

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watch -n <seconds> <command>
2009-09-04 15:19:42
User: aonick
Functions: watch
Tags: bash
-2
Up
Down
bash function to check for something every 5 seconds

Every seconds do

Show sample output | Comments (1) | Add to favourites | Report as malicious | Submit alternative | Report as a duplicate
watch -d 'ls -l'
2009-09-03 20:12:36
User: 0disse0
Functions: watch
Tags: watch stats
0
Up
Down
How to watch files

To highlight the difference between screen updates

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watch 'cat /proc/loadavg'
2009-09-03 20:10:46
User: 0disse0
Functions: watch
Tags: status watch
1
Up
Down
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

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watch --interval 0 'iptables -nvL | grep -v "0 0"'
2009-08-22 18:18:05
User: Code_Bleu
Functions: grep watch
Tags: grep iptables watch invert-filter
4
Up
Down
watch iptables counters

This will allow you to watch as matches occur in real-time. To filter out only ACCEPT, DROP, LOG..etc, then run the following command: watch 'iptables -nvL | grep -v "0 0" && grep "ACCEPT"' The -v is used to do an inverted filter. ie. NOT "0 0"

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watch -n .5 "iwlist wlan0 scan"
2009-08-20 23:05:04
User: Abiden
Functions: watch
1
Up
Down
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.

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