How to write a .sh that get process id of application and then stop the application? - sh

for example, I need to use a app called SomeApp, but it often needs to restart, so I need to type "ps -ef | grep SomeApp" and then "kill -9 7777"
which first find the process id and then stop that process:
XXXX:~ XXXX$ ps -ef | grep SomeApp
333 7777 1 0 1:40PM ?? 0:40.31 /Users/XXXX/SomeApp
333 8888 9999 0 1:58PM abcd000 0:00.00 grep SomeApp
XXXX:~ XXXX$ kill -9 7777
now I want to put the command into .sh, but I have something don't know how to write in .sh:
exclude the result that belongs to my grep action
get the correct line result
get the second argument (process id) of result string
can anyone help?

This'll do it.
ps -ef | grep 'SomeApp' | grep -v grep | awk '{print $2}' | xargs kill
Or look at pgrep and pkill depending on the OS.

Related

How do I automate killing a job in cron? [duplicate]

This question already has answers here:
Find and kill a process in one line using bash and regex
(30 answers)
Closed 1 year ago.
Sometimes when I try to start Firefox it says "a Firefox process is already running". So I have to do this:
jeremy#jeremy-desktop:~$ ps aux | grep firefox
jeremy 7451 25.0 27.4 170536 65680 ? Sl 22:39 1:18 /usr/lib/firefox-3.0.1/firefox
jeremy 7578 0.0 0.3 3004 768 pts/0 S+ 22:44 0:00 grep firefox
jeremy#jeremy-desktop:~$ kill 7451
What I'd like is a command that would do all that for me. It would take an input string and grep for it (or whatever) in the list of processes, and would kill all the processes in the output:
jeremy#jeremy-desktop:~$ killbyname firefox
I tried doing it in PHP but exec('ps aux') seems to only show processes that have been executed with exec() in the PHP script itself (so the only process it shows is itself.)
pkill firefox
More information: http://linux.about.com/library/cmd/blcmdl1_pkill.htm
Also possible to use:
pkill -f "Process name"
For me, it worked up perfectly. It was what I have been looking for.
pkill doesn't work with name without the flag.
When -f is set, the full command line is used for pattern matching.
You can kill processes by name with killall <name>
killall sends a signal to all
processes running any of the specified
commands. If no signal name is
specified, SIGTERM is sent.
Signals can be specified either by
name (e.g. -HUP or -SIGHUP ) or by number (e.g.
-1) or by option -s.
If the command name is not regular
expression (option -r) and contains a
slash (/), processes executing that
particular file will be selected for
killing, independent of their name.
But if you don't see the process with ps aux, you probably won't have the right to kill it ...
A bit longer alternative:
kill `pidof firefox`
The easiest way to do is first check you are getting right process IDs with:
pgrep -f [part_of_a_command]
If the result is as expected. Go with:
pkill -f [part_of_a_command]
If processes get stuck and are unable to accomplish the request you can use kill.
kill -9 $(pgrep -f [part_of_a_command])
If you want to be on the safe side and only terminate processes that you initially started add -u along with your username
pkill -f [part_of_a_command] -u [username]
Kill all processes having snippet in startup path. You can kill all apps started from some directory by for putting /directory/ as a snippet. This is quite usefull when you start several components for the same application from the same app directory.
ps ax | grep <snippet> | grep -v grep | awk '{print $1}' | xargs kill
* I would prefer pgrep if available
Strange, but I haven't seen the solution like this:
kill -9 `pidof firefox`
it can also kill multiple processes (multiple pids) like:
kill -9 `pgrep firefox`
I prefer pidof since it has single line output:
> pgrep firefox
6316
6565
> pidof firefox
6565 6316
Using killall command:
killall processname
Use -9 or -KILL to forcefully kill the program (the options are similar to the kill command).
On Mac I could not find the pgrep and pkill neither was killall working so wrote a simple one liner script:-
export pid=`ps | grep process_name | awk 'NR==1{print $1}' | cut -d' ' -f1`;kill $pid
If there's an easier way of doing this then please share.
To kill with grep:
kill -9 `pgrep myprocess`
more correct would be:
export pid=`ps aux | grep process_name | awk 'NR==1{print $2}' | cut -d' ' -f1`;kill -9 $pid
I normally use the killall command.
Check this link for details of this command.
I was asking myself the same question but the problem with the current answers is that they don't safe check the processes to be killed so... it could lead to terrible mistakes :)... especially if several processes matches the pattern.
As a disclaimer, I'm not a sh pro and there is certainly room for improvement.
So I wrote a little sh script :
#!/bin/sh
killables=$(ps aux | grep $1 | grep -v mykill | grep -v grep)
if [ ! "${killables}" = "" ]
then
echo "You are going to kill some process:"
echo "${killables}"
else
echo "No process with the pattern $1 found."
return
fi
echo -n "Is it ok?(Y/N)"
read input
if [ "$input" = "Y" ]
then
for pid in $(echo "${killables}" | awk '{print $2}')
do
echo killing $pid "..."
kill $pid
echo $pid killed
done
fi
kill -9 $(ps aux | grep -e myprocessname| awk '{ print $2 }')
If you run GNOME, you can use the system monitor (System->Administration->System Monitor) to kill processes as you would under Windows. KDE will have something similar.
The default kill command accepts command names as an alternative to PID. See kill (1). An often occurring trouble is that bash provides its own kill which accepts job numbers, like kill %1, but not command names. This hinders the default command. If the former functionality is more useful to you than the latter, you can disable the bash version by calling
enable -n kill
For more info see kill and enable entries in bash (1).
ps aux | grep processname | cut -d' ' -f7 | xargs kill -9 $
awk oneliner, which parses the header of ps output, so you don't need to care about column numbers (but column names). Support regex. For example, to kill all processes, which executable name (without path) contains word "firefox" try
ps -fe | awk 'NR==1{for (i=1; i<=NF; i++) {if ($i=="COMMAND") Ncmd=i; else if ($i=="PID") Npid=i} if (!Ncmd || !Npid) {print "wrong or no header" > "/dev/stderr"; exit} }$Ncmd~"/"name"$"{print "killing "$Ncmd" with PID " $Npid; system("kill "$Npid)}' name=.*firefox.*

Check number of active meetings in Big Blue Button from command line

I want to check how many active meetings there are on the BBB server at any one time from the command line. I have tried
$ bbb-conf --network
but not getting anywhere. I have also checked the number of active connections to port 80 and 443
$ netstat -anp | grep :443 | grep ESTABLISHED | wc -l
but I'm not sure if I can trust that figure.
I know I can use the isMeetingRunning call from the API but I'm just looking for command line.
Any ideas would be appreciated
The following bash script, which can be run from command line on the same machine as the BigBlueButton server, will process the response to the BBB API getMeetings call.
#!/bin/bash
APICallName="getMeetings"
APIQueryString=""
X=$( bbb-conf --secret | fgrep URL: )
APIEndPoint=${X##* }
Y=$( bbb-conf --secret | fgrep Secret: )
Secret=${Y##* }
S=$APICallName$APIQueryString$Secret
Checksum=$( echo -n $S | sha1sum | cut -f 1 -d ' ' )
if [[ "$APIQueryString" == "" ]]
then
URL="${APIEndPoint}api/$APICallName?checksum=$Checksum"
else
URL="${APIEndPoint}api/$APICallName?$APIQueryString&checksum=$Checksum"
fi
wget -q -O - "$URL" | grep -o '<meetingID>' | wc -w
Tested on a live BBB machine.
Note:
The APICallName and APIQueryString can be modified to provide interface to other BBB API calls. See https://docs.bigbluebutton.org/dev/api.html
The command-line sha1sum will output a different result if a newline is appended to its input. This is the reason echo -n is used instead of echo.
In the last line, the script processes the XML output from the API call in a very naïve way, simply counting the number of occurences of the <meetingID> tag. More elaborate processing would probably require parsing the XML.

multiple grep command in Linux

Just a basic question about grep command line. I found the way how to know that the service is running in process by using this command line:
ps -ef |grep -v grep | grep mongodb
I'm confused about the second grep:
|grep -v grep |
Why I need to use the "grep" after " -v " ???
What is the different between that command and this command ?
ps -ef |grep mongodb
Thank you!
When you grep "mongodb" through command line, your command also contains the word "mongodb" . So you will get two results. Which is flawed result. grep -v is to remove the grep command typed by user.
sh-4.1$ ps -ef |grep -v grep | grep mongodb
ps 17308 30074 0 06:05 pts/300 00:00:00 sh mongodb
vs
sh-4.1$ ps -ef |grep mongodb
ps 17308 30074 0 06:05 pts/300 00:00:00 sh mongodb
ps 17456 30074 0 06:05 pts/300 00:00:00 grep mongodb #<<<This also contains mongodb word. Hence result is flawed.
The -v option tells grep not to let through anything matching the pattern, in this case lines that contain the string "grep".
So if you omit the grep -v grep
your grep process itself would also be displayed in the output after the second command in the pipe (and also after the third, as the grep process itself contains the word "mongodb").

Can't kill celery workers

Try as I might I cannot kill these celery workers.
I run:
celery --app=my_app._celery:app status
I see I have 3 (I don't understand why 3 workers = 2 nodes, please explain if you know)
celery#ip-x-x-x-x: OK
celery#ip-x-x-x-x: OK
celery#named-worker.%ip-x-x-x-x: OK
2 nodes online.
I run (as root):
ps auxww | grep 'celery#ip-x-x-x-x' | awk '{print $2}' | xargs kill -9
The workers just keep reappearing with a new PID.
Please help me kill them.
A process whose pid keeps changing is called comet. Even though pid of this process keeps on changing, its process group ID remains constant. So you can kill by sending a signal.
ps axjf | grep '[c]elery' | awk '{print $3}' | xargs kill -9
Alternatively, you can also kill with pkill
pkill -f celery
This kills all processes with fullname celery.
Reference: killing a process
pkill -f celery
Run from the command line, this will kill at processes related to celery.
In your console, type :
ps -aux | grep celery
I get :
simon 24615 3.8 0.6 344276 219604 pts/3 S+ 22:53 0:56 /usr/bin/python3 /home/simon/.local/bin/celery -A worker_us_task worker -l info -Q us_queue --concurrency=30 -n us_worker#%h
select what you find after -A and type :
pkill -9 -f 'worker_us_task worker'
I always use:
ps auxww | grep 'celery' | awk '{print $2}' | xargs kill -9
If you're using supervisord to run celery, you need to kill supervisord process also.

Using /proc/<pid>, how can I identify a network port number's application?

I'm trying to identify what application is running on port 56474 without having root access. I know the application was started by me.
Example:
netstat -tunap
tcp 0 0 0.0.0.0:56474 0.0.0.0:* LISTEN -
I've tried using /proc/pid scripts to walk all using grep on ls -l /proc/pid/fd results. Here is my attempt. NOTE: Not sure if I was heading the right direction
for I in `find /proc/*/fd -exec ls -l {} \; 2>/dev/null | awk -F"->|:" '/socket/ {print $4}' | sort -u | sed -e 's/\[//g' -e 's/\]//g'`; do grep $I /proc/*/net/tcp; done
I had no success. Not sure if there is a way. Thanks.
NOTE: Added another answers as lsof was not satisfactory.
This should work:
#! /bin/bash
port=56474
hex_port=$(echo "obase=16; $port" | bc )
inode=$(cat /proc/net/tcp | grep ":$hex_port" | awk '{print $10}')
for i in $(ps axo pid); do
ls -l /proc/$i/fd 2> /dev/null | grep -q ":\[$inode\]" && echo $i
done
Explanation:
Once we have the port number converted to Hexadecimal, we can get the inode number from /proc/net/tcp (10th field), then we loop through /proc/pids/fd and find a symlink pointing to the inode.
If you're sure the application was started by you then you can use lsof:
/usr/sbin/lsof -nP | grep :56474 | awk '{print $2}'
Another technique to resolve pids and ports of all running apps without root:
1.) Get the pids of running apps. Either use the ActivityManager or parse a ps console output.
2.) iterate through /proc/$pid/net/status files and get the matching uid for a pid.
cat /proc/*pid*/net/status | grep Uid:
3.) Call and parse the output of tcp, tcp6,udp, udp6 files to match ports and uids:
cat /proc/net/tcp
...
4.) match the uids of both matchings, get a port-to-pid map without su access.
Cheers,
goethe