Killing process automatically

kais1 · 07-30-2011, 11:29 AM

Dear all,

I have a log file which gives some info like

11/07/30 06:13:55 [libopmnoc4j] OC4J ping attempt timed out
11/07/30 06:13:55 [libopmnoc4j] Process Ping Failed: default_group~OC4J_CMG~default_group~1 (1080848993:28956)

I need a script to constantly monitor this log file and look for the above files. if the file is getting any new
messages like above, it has to take the process id from the line

[libopmnoc4j] Process Ping Failed: default_group~OC4J_CMG~default_group~1 (1080848993:28956)

which is 28956 and do kill -9 28956 automatically/immediately.

I need to your expert guidance to achieve the same .

Thanks
Kai

Snark1994 · 07-30-2011, 12:29 PM

Try something like:

Code:

while [[ 1 == 1 ]]; do
    rev /path/to/log/file | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
    if [ $? ]; then
        PID=$(rev /path/to/log/file | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
        if kill -9 $PID > /dev/null 2>&1; then
            echo "Killed $PID"
        fi
    fi
    sleep 1
done

Hope this helps,

kais1 · 07-30-2011, 02:01 PM

Quote:

Originally Posted by Snark1994

Try something like:

Code:

while [[ 1 == 1 ]]; do
    rev /path/to/log/file | grep "$(date +"%y/%m/%d %H:%M:%S).*Process Ping Failed:"
    if [ $? ]; then
        PID=$(rev /path/to/log/file | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
        if kill -9 $PID > /dev/null 2>&1; then
            echo "Killed $PID"
        fi
    fi
    sleep 1
done

Hope this helps,

<dapps02]orasoa:medt/appl/1013/opmn/logs> sh opmn.sh
opmn.sh: syntax error at line 3: `)' unexpected
<dapps02]orasoa:medt/appl/1013/opmn/logs> cat opmn.sh
#!/bin/sh
while [[ 1 == 1 ]]; do
rev medt/appl/1013/opmn/logs/opmn.log | grep "$(date +"%y/%m/%d %H:%M:%S).*Process Ping Failed:"
if [ $? ]; then
PID=$(rev medt/appl/1013/opmn/logs/opmn.log | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
if kill -9 $PID > /dev/null 2>&1; then
echo "Killed $PID"
fi
fi
sleep 1
done

Any idea ?

Kai

Snark1994 · 07-30-2011, 02:05 PM

Sorry, I missed a quote - I've amended the original code. It should be:

Code:

grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"

not

Code:

grep "$(date +"%y/%m/%d %H:%M:%S).*Process Ping Failed:"

Apologies,

kais1 · 07-30-2011, 02:11 PM

Quote:

Originally Posted by Snark1994

Sorry, I missed a quote - I've amended the original code. It should be:

Code:

grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"

not

Code:

grep "$(date +"%y/%m/%d %H:%M:%S).*Process Ping Failed:"

Apologies,

Thanks Snark,

Am getting the below error now

opmn.sh: syntax error at line 5: `PID=$' unexpected

Kai

Snark1994 · 07-30-2011, 02:20 PM

Can you post the code you're running? I can't run the code I posted for you (I don't have either the log file or processes to kill), but this works for me without complaining:

Code:

#!/bin/sh
while [[ 1 == 1 ]]; do
    rev tt | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
    PID=$(rev tt | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
    sleep 1
done

If you can run the above code but not what you've got in your script then I'll have to do some thinking about how I can debug it more carefully

kais1 · 07-30-2011, 02:24 PM

Quote:

Originally Posted by Snark1994

Can you post the code you're running? I can't run the code I posted for you (I don't have either the log file or processes to kill), but this works for me without complaining:

Code:

#!/bin/sh
while [[ 1 == 1 ]]; do
    rev tt | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
    PID=$(rev tt | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
    sleep 1
done

If you can run the above code but not what you've got in your script then I'll have to do some thinking about how I can debug it more carefully

Thanks Snark

[/CODE]

#!/bin/sh
while [[ 1 == 1 ]]; do
rev /fraud/appl/orasoa/1013/opmn/logs/opmn.log | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
if [ $? ]; then
PID=$(rev /fraud/appl/orasoa/1013/opmn/logs/opmn.log | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
if kill -9 $PID > /dev/null 2>&1; then
echo "Killed $PID"
fi
fi
sleep 1
done

[/CODE]

Tried running the below

[/CODE]

#!/bin/sh
while [[ 1 == 1 ]]; do
rev tt | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
PID=$(rev tt | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
sleep 1
done
[/CODE]

Am getting the same error

Thanks
Kai

Snark1994 · 07-30-2011, 02:43 PM

Hm, I just noticed that my /bin/sh is symlinked to bash. Perhaps try running it using "#!/bin/bash" or "#!/usr/bin/bash" (depending where bash is on your system). That's all I can think of, I'm afraid.

As a note: To open a code tag, it's "[ CODE ]" not "[ / CODE ]" (without spaces)

kais1 · 07-30-2011, 02:55 PM

Quote:

Originally Posted by Snark1994

Hm, I just noticed that my /bin/sh is symlinked to bash. Perhaps try running it using "#!/bin/bash" or "#!/usr/bin/bash" (depending where bash is on your system). That's all I can think of, I'm afraid.

As a note: To open a code tag, it's "[ CODE ]" not "[ / CODE ]" (without spaces)

Thanks Snark,

Tried using both "#!/bin/bash" and "#!/usr/bin/bash"

[CODE]
"opmn.sh" 11 lines, 417 characters
#!/usr/bin/bash
while [[ 1 == 1 ]]; do
rev /fraud/appl/orasoa/1013/opmn/logs/opmn.log | grep "$(date +"%y/%m/%d %H:%M:%S").*Process Ping Failed:"
if [ $? ]; then
PID=$(rev /fraud/appl/orasoa/1013/opmn/logs/opmn.log | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')
if kill -9 $PID > /dev/null 2>&1; then
echo "Killed $PID"
fi
fi
sleep 1
done
[CODE]

Am still getting the same error

<frdapps02]orasoa:/fraud/appl/orasoa/1013/opmn/logs> sh opmn.sh
opmn.sh: syntax error at line 4: `PID=$' unexpected

Kai

Snark1994 · 07-30-2011, 03:02 PM

Ah, but you're still calling it with "sh" - try running

Code:

bash opmn.sh

instead.

And nearly there with the code tags - I can't write it in the forum, because it goes funny about it in the forum. If you run:

Code:

printf "\x5BCODE\x5Dyour code in here\x5B/CODE\x5D\n"

then it will print out what it should look like

kais1 · 07-30-2011, 03:34 PM

Quote:

Originally Posted by Snark1994

Ah, but you're still calling it with "sh" - try running

Code:

bash opmn.sh

instead.

And nearly there with the code tags - I can't write it in the forum, because it goes funny about it in the forum. If you run:

Code:

printf "\x5BCODE\x5Dyour code in here\x5B/CODE\x5D\n"

then it will print out what it should look like

Sorry to bother you again.. But am getting a different error

<frdapps02]orasoa:/fraud/appl/orasoa/1013/opmn/logs> bash opmn.sh
opmn.sh: line 3: rev: command not found
opmn.sh: line 5: rev: command not found
grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . .
opmn.sh: line 3: rev: command not found
opmn.sh: line 5: rev: command not found
grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . .
opmn.sh: line 3: rev: command not found
opmn.sh: line 5: rev: command not found
grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . .
opmn.sh: line 3: rev: command not found
opmn.sh: line 5: rev: command not found
grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . .
opmn.sh: line 3: rev: command not found
opmn.sh: line 5: rev: command not found
grep: illegal option -- o
Usage: grep -hblcnsviw pattern file . . .

Kai

Snark1994 · 07-30-2011, 03:57 PM

No need to apologise - I'm the one who's not being very good at giving advice, eh

this now comes down to the version of utilities that you have... I use the "util-linux" package (from http://ftp://ftp.kernel.org/pub/linux/utils/util-linux/) which contains 'rev'; certainly there's a "util-linux" package available for Ubuntu and Arch (my distribution of choice), I don't know what distribution you run. For grep:

Code:

$ grep --version
grep (GNU grep) 2.9
Copyright (C) 2011 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by Mike Haertel and others, see <http://git.sv.gnu.org/cgit/grep.git/tree/AUTHORS>.

How does that compare with your version? You could maybe try 'egrep' rather than 'grep', see if your version of that supports the '-o' flag (which prints only the parts of the line which match the pattern, rather than the whole line).

chrism01 · 07-31-2011, 07:20 PM

From post #9

Code:

PID=$(rev /fraud/appl/orasoa/1013/opmn/logs/opmn.log | grep "Process Ping Failed:" | grep -o ":[0-9]*)" | sed 's/://; s/)//')


# summarized
PID=$( rev ...) | sed .... )..)

# unbalanced brackets

I'd be a little worried that your loop is not going to miss or dupe any instances; depends how fast it loops.
I'd base my soln on 'tail -f' or use the Perl module http://search.cpan.org/~mgrabnar/Fil...0.99.3/Tail.pm

Snark1994 · 08-01-2011, 04:07 AM

I'm not quite sure if I misunderstand your objections... The brackets are quoted, so it's more like:

Code:

#summarized
PID=$( rev ... | grep -o "...)" | sed 's/)//')

Is this still likely to cause problems?

And it's going to keep on going from the end of the file backwards until it finds the latest match - are you just worried that it might spawn two processes which need deleting before it wraps around again? It definitely will hit the same process more than once, but I didn't think this would be an issue as it's already killed the process. However, it did strike me as remarkably inelegant - could you just demonstrate how you could feed 'tail -f' into a loop?

chrism01 · 08-01-2011, 06:19 PM

Ok, you may be right about the brackets; its a messy line to read

Re tail -f, something like this (untested)

Code:

tail -f myfile.log|grep/awk <pattern grab pid>|kill

you get the general idea.
The -f switch means follow, so you don't need a loop.

Your orig idea would keep on trying to kill the the same process, leading to extra load on the cpu and spurious error msgs about pid nor found etc, if its quick.
If its slow, it may miss some...

The Perl module gives you a nice clean, controlled soln and you can log more info eg how many killed, how often etc.
BTW, isn't there anyway to cut down/eliminate those failures in the first place ie fix the prob rather than the symptom?