Cronjob Created Empty Files

I have a small script1 scheduled via cron to run every 20 mins to invoke script2 if script2 is not running.
When i run script1 from cmd line it works fine but when it is scheduled via cron it doesn't work. Not sure what am i doing wrong here.
I even tried to use absolute path.

Script 1
Code:

#!/bin/sh
/bin/ps -ef |/bin/grep script2.sh |/bin/grep -v $$ > /dev/null 2>&1
if [ $? -ne 0 ]
then
/usr/bin/nohup /home/user1/script2.sh &
fi

CRON LOG :
Feb 9 17:00:01 server1 crond[29771]: (user1) CMD (/home/user1/chk_script1.sh >/dev/null 2>&1)
Feb 9 17:20:01 server1 crond[21095]: (user1) CMD (/home/user1/chk_script1.sh >/dev/null 2>&1)
Feb 9 17:40:01 server1 crond[11218]: (user1) CMD(/home/user1/chk_script1.sh >/dev/null 2>&1)
Feb 9 18:00:01 server1 crond[29961]: (user1) CMD(/home/user1/chk_script1.sh >/dev/null 2>&1)

CRON JOB :
00,20,40 * * * * /home/user1/chk_script1.sh >/dev/null 2>&1

Hello,

I cannot understand why the symlink I have put in /etc/cront.daily won't work. It is very possible I am wrong, but my understanding is that cront.{daily,weekly,monthly} works fine with symlinks.

Basically it is double symlink-ed. ls -la on /etc/cron.daily looks like this:

Code:

... 
lrwxrwxrwx  1 root root    49 Nov 27 18:26 rsync_mysql_backups.sh -> /home/myuser/scripts/bash/rsync_mysql_backups.sh
...

Now, ls -la on /home/myuser/scripts looks like this:

Code:

...
lrwxrwxrwx 1 myuser myuser    26 Sep 20  2013 scripts -> /media/md1_storage/scripts
...

I couldn't see anything suspicious in syslog, so I installed postfix in the hope that I will get some sort of information there. Nothing... I also redirected the output of the script to a file in /home/myuser/log.txt but nothing there. The file was not even created.

I am not doing anything mad in the script, I am just synchronising a local directory with a remote one like this:

Code:

/usr/bin/rsync -avzx -e 'ssh -i "/home/myuser/.ssh/myremotehost/id_rsa"' /media/md1_storage/backups/stuff/ myuser@myremotehost:/srv/backups/stuff/ >> /home/myuser/log.txt 2>&1;

As other people suggested in similar threads, I have verified that
Code:

test -x /usr/sbin/anacron

is false, which will result in the execution of the second part of the entry in /etc/crontab:

Code:

25 6    * * *   root    test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )

Any input will be much appreciated. I know I am doing something wrong, but I just cannot see it right now... How can I gather more debugging which will help me understand what's going wrong?

Thanks!

Hi,

i have a small problem on my system... I recently wrote a small bash script and added it via crontab -u root -e and it's executed as it should.
Then a few days after i did edit my bash script, but once it is run by cron it doesn't reflect the changes i made to the script. I did manually restart crond, tryed sync, moved my script, renamed it even rstart the server - no success.
If i run my script manually it returns me the expected output.
part of my script (/root/sd.sh):
Code:

#!/bin/sh

echo -n "Checking Raid... "
RAID=`tw-cli /c0/u0 show status | cut -c17-31 | grep -ci OK`
RAIDSTATUS=`tw-cli /c0/u0 show status | head -n1 | cut -c17-31`
if [ $RAID -eq 0 ]; then
  VERIFYING=`tw-cli /c0/u0 show status | cut -c17-31 | grep -ci VERIFYING`
  REBUILDING=`tw-cli /c0/u0 show status | cut -c17-31 | grep -ci REBUILDING`
  if [ $VERIFYING -eq 1 ]; then
    CURRENTSTATUS=`tw-cli /c0/u0 show verifystatus | head -n1 | cut -c46-49`
  fi
  if [ $REBUILDING -eq 1 ]; then
    CURRENTSTATUS=`tw-cli /c0/u0 show rebuildstatus | head -n1 | cut -c47-50`
  fi
  echo "Raid is busy (Raid $RAIDSTATUS$CURRENTSTATUS)"
  exit 1
fi
echo "Raid is idle (Raid $RAIDSTATUS)"

echo -n "Checking for logged in Users... "
USERS=`who | wc -l`
if [ $USERS -gt 0 ]; then
  echo "Users online"
  exit 1
fi
echo "None logged in"

crontab -l :
Code:

root@monster:~# crontab -l
# Edit this file to introduce tasks to be run by cron.
#
# Each task to run has to be defined through a single line
# indicating with different fields when the task will be run
# and what command to run for the task
#
# To define the time you can provide concrete values for
# minute (m), hour (h), day of month (dom), month (mon),
# and day of week (dow) or use '*' in these fields (for 'any').#
# Notice that tasks will be started based on the cron's system
# daemon's notion of time and timezones.
#
# Output of the crontab jobs (including errors) is sent through
# email to the user the crontab file belongs to (unless redirected).
#
# For example, you can run a backup of all your user accounts
# at 5 a.m every week with:
# 0 5 * * 1 tar -zcf /var/backups/home.tgz /home/
#
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h  dom mon dow   command
*/10 * * * * /root/sd.sh | logger
*/30 * * * * /root/dropbox.sh > /dev/null

syslog:
Code:

Mar 21 09:10:01 monster /USR/SBIN/CRON[3998]: (root) CMD (/root/sd.sh | logger)
Mar 21 09:10:01 monster logger: Checking Raid... Raid is busy (Raid )
Mar 21 09:17:01 monster /USR/SBIN/CRON[4045]: (root) CMD (   cd / && run-parts --report /etc/cron.hourly)
Mar 21 09:20:01 monster /USR/SBIN/CRON[4105]: (root) CMD (/root/sd.sh | logger)
Mar 21 09:20:01 monster logger: Checking Raid... Raid is busy (Raid )
Mar 21 09:30:01 monster /USR/SBIN/CRON[4266]: (root) CMD (/root/sd.sh | logger)
Mar 21 09:30:01 monster /USR/SBIN/CRON[4265]: (root) CMD (/root/dropbox.sh > /dev/null)
Mar 21 09:30:01 monster logger: Checking Raid... Raid is busy (Raid )

when i run sh /root/sd.sh
Code:

root@monster:~# sh /root/sd.sh
Checking Raid... Raid is idle (Raid OK)
Checking for logged in Users... Users online
root@monster:~#

Any ideas why? - any help or thoughts appreciated

regards
Pat

I am trying to delay the daily reboot of multiple Linux machines by a random time, within one hour.

This is to avoid a simultaneous reboot of all the Linux machines at the same time.

I also want to avoid specifying a time in cron. I want it to be completely random between 00:00 and 01:00.

So far I tried the commands below, but no luck. The machines still reboot at midnight.

Code:

@daily /bin/sleep $((RANDOM\%3600)) && /sbin/reboot
@daily /bin/sleep $(/usr/bin/expr $RANDOM \% 3600); /bin/reboot

I see that you can set CRON jobs to run hourly etc, but I don't see any exapmles of setting one up to start and stop at specified times.

The job I want while run continuously, once started at 6pm, until all of the records are processed or until 6am.

Can this be done?

If so, how?

PS. 6 months ago I couldn't even spell LINUX.

Hi All,

I have perl script which I am trying to run on 1st Monday via cron job.
So I scheduled it as follows:

0 0 1-7 * * root ["$(date '+%a')" = "Mon"] && /usr/bin/perl script.pl

But then it didn't run so checked cron log and it seemed like its missing the command. so added a \ in front of %a and then it picked up the whole command as per cron log.

But still it didnt ran the script. I then change the script to just && echo "test">/tmp/test

Still nothing. if I run it as /usr/bin/perl script.pl it runs though

Thanks in advance.

I am porting linux on movidius M2 leon3 board,but unable to get login prompt I am only getting /etc/issue message
as below

UART: --> do_sys_open /etc/issue f1935ec0
UART: --> do_sys_open /etc/issue f1935ec0
UART: IamHere 3
UART: IamHere 3
UART: Welcome to Buildroot

No login prompt

my inittab script as below

# completely ignored by BusyBox init. If you want runlevels, use
# sysvinit.
#
# Format for each entry: <id>:<runlevels>:<action>:<process>
#
# id == tty to run on, or empty for /dev/console
# runlevels == ignored
# action == one of sysinit, respawn, askfirst, wait, and once
# process == program to run

# Startup the system
null::sysinit:/bin/mount -t proc proc /proc
null::sysinit:/bin/mount -o remount,rw / # REMOUNT_ROOTFS_RW
null::sysinit:/bin/mkdir -p /dev/pts
null::sysinit:/bin/mkdir -p /dev/shm
null::sysinit:/bin/mount -a
null::sysinit:/bin/hostname -F /etc/hostname
# now run any rc scripts
::sysinit:/etc/init.d/rcS
#ttyS::sysinit:/bin/echo "I am Manjunath to let this work."
#ttyS::respawn:/sbin/getty -L ttyS0 38400 vt100
# Example of how to put a getty on a serial line (for a terminal)
#::respawn:/sbin/getty -L ttyS0 9600 vt100
#::respawn:/sbin/getty -L ttyS1 9600 vt100
#
# Example how to put a getty on a modem line.
#::respawn:/sbin/getty 57600 ttyS2
ttyS0::respawn:/bin/sh </dev/ttyS0 >/dev/ttyS0 2>/dev/ttyS0
# Put a getty on the serial port
#ttyS0::askfirst:/bin/sh
#ttyS::respawn:/bin/sh </dev/ttyS0 >/dev/ttyS0 2>&1
ttyS0::respawn:/sbin/getty -n ttyS0 38400 vt100 # GENERIC_SERIAL
#ttyS::wait:/bin/sh </dev/ttyS0 >/dev/ttyS0 2>&1

# Logging junk
null::sysinit:/bin/touch /var/log/messages
null::respawn:/sbin/syslogd -n -m 0
null::respawn:/sbin/klogd -n
#null::sysinit:/bin/touch /var/log/messages
#null::wait:/sbin/syslogd -n -m 0
#null::respawn:/sbin/klogd -n

# Stuff to do for the 3-finger salute
::ctrlaltdel:/sbin/reboot

# Stuff to do before rebooting
null::shutdown:/usr/bin/killall klogd
null::shutdown:/usr/bin/killall syslogd
null::shutdown:/bin/umount -a -r
null::shutdown:/sbin/swapoff -a

Is any problem in my inittab.
please help me to get from this issue.

Thanks
Manjunath Goudar

Hi ,

Please explain what the below command means ..


Code:

if grep -c -i Y $INIFILE > /dev/null

I know what is the use of grep, it is used for finding a character or string in a file. But i could not understand the above form of grep command.

I am new to linux so this might be a simple question, but please throw some light on it.


Edited

And also please explain why they are creating a file in null in the below command

Code:

cat /dev/null > $DATA_DIR/$DATAFILE

For the below code, I observe that when pthread_join is commented from the code - the order of thread execution is not consistent (the main thread executes first and then the remaining threads - in what sequence I am not sure). But when pthread_join is present in the code - I see that order of execution of the threads is as per the code (First t1, then t2 and finally main exits....I can tell that for sure by observing the increasing value of id in main())

Can anybody tell me why that happens?


#include <pthread.h>
#include <stdio.h>
pthread_once_t once = PTHREAD_ONCE_INIT;

void *myinit()
{
printf("\n I am in init\n");
}

void* t1routine(void* i)
{
printf("\n I am in thread%d\n", *(int*)i);
pthread_once(&once, (void*)myinit);
printf("\n I am exiting from thread %d\n", *(int*)i);
}

void* t2routine(void* i)
{
printf("\n I am in thread%d\n", *(int*)i);
pthread_once(&once, (void*)myinit);
printf("\n I am exiting from thread %d\n", *(int*)i);
}

void* t3routine(void* i)
{
printf("\n I am in thread%d\n", *(int*)i);
pthread_once(&once, (void*)myinit);
printf("\n I am exiting from thread %d\n", *(int*)i);
}

main()
{
int id = 1;
pthread_t t1,t2,t3;
pthread_create(&t1, NULL, t1routine, (void*) &id);
pthread_join(t1, NULL);
id++;

pthread_create(&t2, NULL, t2routine, (void*) &id);
pthread_join(t2, NULL);
id++;

pthread_create(&t3, NULL, t3routine, (void*) &id);
pthread_join(t3, NULL);
pthread_exit(NULL);
}

Hi All,

I have two scripts, the aim of these two scripts is, to check whether a particular script is running or not, if it wont runs, then throw a mail.

How i Achieved this output is, I wrote first script.

I created an infinite while loop which performs below steps

1. It creates a touch file
2. Triggers the script which needs to be monitored if its working or not.
3. Removes the touch file.

If the second step fails, then the remove file command will not happen and the script will stuck there itself.

I created an another script which checks the creation time of the touch file and if it is more than ten minutes, it means the second step in the first script is hanged, which also means that particular script is not working.

So if the creation time is more than 2 minutes the second script will throw a mail.

Below are the two scripts.

Code:

#!/bin/ksh



userid="chansd"

filename="/apps/log/check.txt"

while true ;do
touch $filename
pass=`/apps/eDMZ/call_st.ksh $userid`
sleep 20
rm $filename
done

Below script checks the file creation time and throws email if it is older than 2 minutes
Code:

#!/bin/ksh


filename="/apps/log/check.txt"

if [ -f "${filename}" ]
then
if test "`find $filename -mmin +2`"
then
echo "script is not working ! Please act on it" | mail -s "Script  is not working" Example@mail.com
fi


else

        exit 1

fi

What im going to do is

1. I am going to run the first script in background so it runs forever.
2. I am going to run the second script in cron forevry 5 mins to check the file creation time.

3. So if the first script hangs . I will kill the process using process id and after the issue resolves with the inner script, I will run the main script again.

I am new to Linux, Please let me know if this approach will work as expected.