Do you get any errors? Running in 'cron' is not like logging in, more like running "ssh user@ost ksh". Your environment is not set up, so commands that work interactively or with a controlling terminal may not run. Usually, the script starts with something like ". ./.profile </dev/null >/dev/null 2>&1" to get environment, but if you need a tty, tougher, maybe "ssh -tt localhost ' ./.profile </dev/null >/dev/null 2>&1;cmd args ....".
Also, 'cron' can discard or email stdout and stderr, so redirect them right off in the crontab line, and maybe everything inside the script as well:
Be careful as '%' is meta in crontab, so it is hard to use date there. I wrote a 'date' wrapper that used '~' for '%', just for 'cron'. If the scripts that cron calls all immediately redirect their logging, you can use a shared log for all crontab lines that is fixed, as it is normally empty. Set up good logging. You deserve it. It is a great investment in your development speed (fast debug) and future (prod support much later).
Last edited by DGPickett; 03-06-2013 at 03:18 PM..
Hi ,
I am having one situation in which I need to run some simple unix commands after doing "chroot" command in a shell script. Which in turn creates a new shell.
So scenario is that
- I need to have one shell script which is ran as a part of crontab
- in this shell script I need to do a... (2 Replies)
Hi Experts,
Can anyone help me to write shell script for taking backup with RMAN in oracle 9i or suggests me any site which has this kind of scripts
Thanks
shaan (1 Reply)
Hi,
I have an HTML form through which I get some text as input. i need to run a shell script say script.sh inside a perl-cgi script named main_cgi.sh on the form input.
I want to write the contents of the form in a file and then perform some command line operations like grep, cat on the text... (2 Replies)
Dears,
I'm new in shell scripting and i need your help, i would like to know how can i create a script to ftp to a certain unix/linux machine/server IP address and get a file for example without user intervention? How can i force the script to use a certain username and password to access this... (4 Replies)
When my script deals with large input files like 22Gb or 18 GB the basic commands like sort or join fails when run from inside the shell scripts. Can there be any specific reason for this?
For e.g.
sort -u -t "," -k1,1 a.csv > a.csv.uniq"
sort -u -t "," -k1,1 b.csv > b.csv.uniq"
The... (3 Replies)
I would like to execute a commands in four different servers through ssh at a single instance(simultaneously).
Below are the details with examples,
ssh user1@server1 "grep xxxx logs"
ssh user1@server2 "grep xxxx logs"
ssh user1@server3 "grep xxxx logs"
Each statement will take some... (4 Replies)
Hi
I have a program
int main(int srgc, char *argv)
{
for(int i=1; i<50; i++)
{
system("dd if=/dev/zero of=file$i bs=1024 count=$i");
}
return 0;
}
My doubt is how to use the "$i" value inside C code
Please help (2 Replies)
Hi,
I have the following RMAN incremental shell script:
# !/bin/bash
export ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1
export ORACLE_SID=ORCL
export PATH=$PATH:${ORACLE_HOME}/bin
rman target=/ << EOF
run {
allocate channel d1 type disk FORMAT... (3 Replies)
Hi,
I have a bash script to run many system commands on CentOS machine, but I am puzzled by some commands had no effect on parent environment.
For example, I want to refresh the desktop xdg menu when some processes added or deleted items from desktop xdg menu. If I run "killall gnome-panel"... (4 Replies)
Discussion started by: hce
4 Replies
LEARN ABOUT REDHAT
cron
CRON(8) System Manager's Manual CRON(8)NAME
cron - daemon to execute scheduled commands (Vixie Cron)
SYNOPSIS
cron
DESCRIPTION
Cron should be started from /etc/rc or /etc/rc.local. It will return immediately, so you don't need to start it with '&'.
Cron searches /var/spool/cron for crontab files which are named after accounts in /etc/passwd; crontabs found are loaded into memory. Cron
also searches for /etc/crontab and the files in the /etc/cron.d/ directory, which are in a different format (see crontab(5)). Cron then
wakes up every minute, examining all stored crontabs, checking each command to see if it should be run in the current minute. When execut-
ing commands, any output is mailed to the owner of the crontab (or to the user named in the MAILTO environment variable in the crontab, if
such exists).
Additionally, cron checks each minute to see if its spool directory's modtime (or the modtime on /etc/crontab) has changed, and if it has,
cron will then examine the modtime on all crontabs and reload those which have changed. Thus cron need not be restarted whenever a crontab
file is modified. Note that the Crontab(1) command updates the modtime of the spool directory whenever it changes a crontab.
SEE ALSO crontab(1), crontab(5)AUTHOR
Paul Vixie <paul@vix.com>
4th Berkeley Distribution 20 December 1993 CRON(8)