How to check last running time of any script in linux instance - linux

I want to check if my scripts ran the last night(or last ran timestamp) on linux instance based on scripts crontab running time stamp.
So how to get scripts last ran time on linux instance?

I would suggest better record the start time during the start of the script and end time at the end of the Script.
# Start Time Entry
echo "Start : " $(date +%T) > exec.log
start=`date +%s`
CALL YOUR SCRIPT HERE
# End Time Entry
end=`date +%s`
echo "End : " $(date +%T) >> exec.log
# Get the Runtime
runtime=$((end-start))
echo "Runtime: $runtime" >> exec.log
If there is any better way, I am also curious to see and implement too.

grep cron from your "messages" or "syslog
grep -i cron /var/log/messages
or create a separate log file for cron from rsyslog, edit file /etc/rsyslog.conf and change #cron to cron. You will find logs in /var/log/cron

Related

Is there a way to get the duration time for a running cronjob?

I want to monitor the long running time cronjob.
enter image description here
You could do:
#!/bin/bash
echo "Starting job blablabla" >>/tmp/job.log
date >>/tmp/duration.log
# THE REST OF THE CODE FOR SCRIPT blablabla
echo "End of job blablabla" >>/tmp/duration.log
date >>/tmp/duration.log
Every execution of the script will add entries with start and end time
Or directly in the cron:
* * * * * time -o /tmp/timing.txt blablabla.sh >/tmp/blablabla.out 2>/tmp/blablabla.out2
time -o shows the resource usage duration for the command.
The -o option specifies which file to send the results into.
The > and 2> redirections are to keep logs of the output and errors. But that is not related to time itself, just a good idea all around with cron jobs.

Cron job stop working after mount operation

I got a simple cron job which simply prints the current date to a log file. For testing purposes, I've done this cron job to occur every minute.
crontab -u user01 -e
* * * * * echo "Date is $(date)" >> /home/user01/date.log
It was used to work before I created a logical volume, give ext4 format to this logical volume and mount it to /home/user01. After the mount operation, it doesn't do anything.
After this, I create a crontab with just (crontab -e), which means I dont give the username , and the crontab started to work again. But I want to know why my first crontab not working after mount.
Also, I know the /home/date.log will be deleted after mount operation but the crontab should write an output to date.log every minute .
For the record, there isn't any problem with mounting. I check /etc/fstab, and df -hT. The /home/user01 directory is mounted.
Also I have tried exact same cron job for another user(user02) in another directory, and it worked so there isn't any syntax or privilige issue.
Also when I check the /var/log/cron, below output come every minute
(user01) CMD (echo "Today is $(date)" >> /home/user01/date.log)
(user02) CMD (echo "Today is $(date)" >> /home/user02/date.log)
This output comes to log file every minute so that I guess the crontab is working but not giving the output for user01 or something.
Thank you for your help
You can login user01 to execute echo "Date is $(date)" >> /home/user01/date.log. success?

Is it possible to auto reboot for 5 loops through mint?

I am currently using the following command to run reboot
sudo shutdown -r now
however, I would need to run it for 5 loops before and after executing some other programs. Was wondering if it is possible to do it in MINT environment?
First a disclaimer: I haven't tried this because I don't want to reboot my machine right now...
Anyway, the idea is to make a script that can track it's iteration progress to a file as #david-c-rankin suggested. This bash script could look like this (I did test this):
#!/bin/sh
ITERATIONS="5"
TRACKING_FILE="/path/to/bootloop.txt"
touch "$TRACKING_FILE"
N=$(cat "$TRACKING_FILE" | wc -c)
if [ "$N" -lt "$ITERATIONS" ]; then
printf "." >> "$TRACKING_FILE"
echo "rebooting (iteration $N)"
# TODO: this is where you put the reboot command
# and anything you want to run before rebooting each time
else
rm "$TRACKING_FILE"
# TODO: other commands to resume anything required
fi
Then add a call to this script somewhere where it will be run on boot. eg. cron (#reboot) or systemd. Don't forget to remove it from a startup/boot command when you're finished or next time you reboot, it will reboot N times.
Not sure exactly how you are planning on using it, but the general workflow would look like:
save script to /path/to/reboot_five_times.sh
add script to run on boot (cron, etc.)
do stuff (manually or in a script)
call the script
computer reboots 5 times
anything in the second TODO section of the script is then run
go back to step 3, or if finished remove from cron/systemd so it won't reboot when you don't want it to.
First create a text document wherever you want,I created one on Desktop,
Then use this file as a physical counter and write a daemon file to run things at startup
For example:
#!/bin/sh
var=$(cat a.txt)
echo "$var"
if [ "$var" != 5 ]
then
var=$((var+1))
echo "$var" > a.txt
echo "restart here"
sudo shutdown -r now
else
echo "stop restart"
echo 0 > a.txt
fi
Hope this helps
I found a way to create a file at startup for my reboot script. I incorporated it with the answers provided by swalladge and also shubh. Thank you so much!
#!/bin/bash
#testing making a startup application
echo "
[Desktop Entry]
Type=Application
Exec=notify-send success
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_CA]=This is a Test
Name=This is a Test
Comment[en_CA]=
Comment=" > ~/.config/autostart/test.desktop
I create a /etc/rc.local file to execute user3089519's script, and this works for my case. (And for bootloop.txt, I put it here: /usr/local/share/bootloop.txt )
First: sudo nano /etc/rc.local
Then edit this:
#!/bin/bash
#TODO: things you want to execute when system boot.
/path/to/reboot_five_times.sh
exit 0
Then it works.
Don't forget edit /etc/rc.local and remove /path/to/reboot_five_times.sh when you done reboot cycling.

How to schedule a jar file on Linux for fixed time in future?

I need to run a jar file (datacollector.jar), say having path (/home/vagrant/datatool) on a Linux machine for a fixed interval of time. For example, from 18:00 10-06-2017 to 03:00 11-06-2017 in some future time. After that, the process should be killed.
I want to write a shell script for this which takes two arguments starting and ending time.
The script should also inform if its already running or not, and I should be able to manually stop it before ending time.
I am unable to figure this out after spending some researching online. How can I achieve this?
I come up with a solution in which myshell.sh take 4 arguments
[start_date] [start_time] [end_date] [end_time].
and script code :
#!/bin/bash
JAR_PATH=/home/vagrant/datatool/datacollector.jar
PID_PATH=/tmp/datacollector-id
#calculate wait time to run the jar
wait=$(($(date -d "$1 $2" "+%s")-$(date "+%s")))
wait_mins=$((wait/60))
#calculate time for which jar file should be executed
run_interval=$(($(date -d "$3 $4" "+%s")-$(date -d "$1 $2" "+%s")))
run_interval_mins=$((run_interval/60))
echo "tool will satrt after $wait_mins"
#wait before running jar file
sleep "$wait_mins"m
#run the jar file
nohup java -jar $JAR_PATH /tmp 2>> /dev/null >> /dev/null &
echo $! > $PID_PATH
#wait for jar execution time
sleep "$run_interval_mins"m
#kill the jar process
PID=$(cat $PID_PATH);
echo "tool process killed"
kill $PID;
echo "program terminated"
and I am running the code with command:
$ nohup ./myshell.sh 2017-06-08 20:07:00 2017-06-08 20:10:00 >> scriptoutput.txt 2>> /dev/null &
and scriptoutput.txt contains:
tool will satrt after 3
tool process killed
program terminated
Where I need to improve my code?
Is there any better way to do it?
There are no wonders: considering your post, you are probably not allowed to modify its source code and recompile it. Thus, you need an external thing, some other process what
starts the jar with a JVM
stops it
informs the user about its start and stop.
The simplest way to do that are the
at command (you can start something in the future with it)
cron command (you can periodically can execute commands with it in the background)
and, the shell scripts.
If it is only a single-time execution, the "at" command would be the best.
Learn about the linux shellscripting by googling for "linux shell scripting tutorial". You can have more specific answers about your problem on the http://unix.stackexchange.com .

How can I trigger a delayed system shutdown from in a shell script?

On my private network I have a backup server, which runs a bacula backup every night. To save energy I use a cron job to wake the server, but I haven't found out, how to properly shut it down after the backup is done.
By the means of the bacula-director configuration I can call a script during the processing of the last backup job (i.e. the backup of the file catalog). I tried to use this script:
#!/bin/bash
# shutdown server in 10 minutes
#
# ps, 17.11.2013
bash -c "nohup /sbin/shutdown -h 10" &
exit 0
The script shuts down the server - but apparently it returns just during the shutdown,
and as a consequence that last backup job hangs just until the shutdown. How can I make the script to file the shutdown and return immediately?
Update: After an extensive search I came up with a (albeit pretty ugly) solution:
The script run by bacula looks like this:
#!/bin/bash
at -f /root/scripts/shutdown_now.sh now + 10 minutes
And the second script (shutdown_now.sh) looks like this:
#!/bin/bash
shutdown -h now
Actually I found no obvious method to add the required parameters of shutdown in the syntax of the 'at' command. Maybe someone can give me some advice here.
Depending on your backup server’s OS, the implementation of shutdown might behave differently. I have tested the following two solutions on Ubuntu 12.04 and they both worked for me:
As the root user I have created a shell script with the following content and called it in a bash shell:
shutdown -h 10 &
exit 0
The exit code of the script in the shell was correct (tested with echo $?). The shutdown was still in progress (tested with shutdown -c).
This bash function call in a second shell script worked equally well:
my_shutdown() {
shutdown -h 10
}
my_shutdown &
exit 0
No need to create a second BASH script to run the shutdown command. Just replace the following line in your backup script:
bash -c "nohup /sbin/shutdown -h 10" &
with this:
echo "/sbin/poweroff" | /usr/bin/at now + 10 min >/dev/null 2>&1
Feel free to adjust the time interval to suit your preference.
If you can become root: either log in as, or sudo -i this works (tested on ubuntu 14.04):
# shutdown -h 20:00 & //halts the machine at 8pm
No shell script needed. I can then log out, and log back in, and the process is still there. Interestingly, if I tried this with sudo in the command line, then when I log out, the process does go away!
BTW, just to note, that I also use this command to do occasional reboots after everyone has gone home.
# shutdown -r 20:00 & //re-boots the machine at 8pm

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