10 More Discussions You Might Find Interesting
1. UNIX for Beginners Questions & Answers
Team,
Hope you all are doing fine
I have one admin server which is being used dedicately to run cron jobs on hourly basis, fetching the details from Database which is in a different server.These cronjob are run on every hourly/5 minutes basis depending as per end user requirement.The script... (12 Replies)
Discussion started by: whizkidash
12 Replies
2. UNIX for Beginners Questions & Answers
on linux redhat, ubuntu systems, what reason would there be for a cron job not running at exactly the time it was scheduled to run, everytime?
meaning, if i put something in cron to run every 120 seconds (2 minutes), why is it that some times, i find that cron would sometimes run the job a few... (1 Reply)
Discussion started by: SkySmart
1 Replies
3. Fedora
Hello, I have several cron jobs scheduled but looking at the results of running I see in some cases it takes more than 2 seconds, is there any way to adjust the accuracy of execution of cron?
Is there any other tool or way to fix the problem? (10 Replies)
Discussion started by: faka
10 Replies
4. Shell Programming and Scripting
Hi
Is it possible to run different cron jobs at the same time? It appears that when I run ones at 15 min granularity that they may prevent ones running later in the day.
Should crons run at same time have impact on one another? (4 Replies)
Discussion started by: rob171171
4 Replies
5. Shell Programming and Scripting
I had a cron file named mycron.cron and this file has cron jobs runs through out 365 days (jobs in the file mycron.cron run hourly, daily, weekly, monthly, quarterly and yearly). Is there an easy way to find what are the jobs scheduled today and what time they are scheduled to run?
Thanks in... (1 Reply)
Discussion started by: sureng
1 Replies
6. OS X (Apple)
I have a cron job set up to run a script on my Leopard Server every night. The job is set up as root, and when I run the script manually, it runs fine.
The problem is that it is not doing anything when it runs at night. In the cron log, it says it ran, but did not output the results to the file it... (3 Replies)
Discussion started by: yodomino6
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7. UNIX for Advanced & Expert Users
Before I get a million and one suggestions on all the things that could be wrong with my scripts - let me assure everyone that this is not the issue.
i have a RH EL ES4 server that stopped running all cron jobs except hourly, daily, weekly.
This has affected all users including root. No... (7 Replies)
Discussion started by: bill_k_Lopez
7 Replies
8. UNIX for Advanced & Expert Users
Good Morning.
The problem started after tha migration to a newer version of oracle - migration to oracle 9i. Before the migration jobs that were scheduled in crontabs were running ok. but after the migration they are not running.
I understand that is not easy to find out what the problem is.... (4 Replies)
Discussion started by: alexcol
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9. UNIX for Dummies Questions & Answers
I have some cron jobs that are taking a might long time. That is because they are screen scrapers and I inserted an extra long pause (10 minutes between screens) to be extra polite and minimize network traffic. I was going to have them run once a day but now I'm thinking once a week.
How do I... (2 Replies)
Discussion started by: siegfried
2 Replies
10. UNIX for Dummies Questions & Answers
I would like to add a job using cron. I have following questions
- cron jobs are launched using what login-id
e.g. is the script launced using my login-id
- In which directory would the cron jobs be launched ?
- where do the environment variables required in the script being lauched come... (3 Replies)
Discussion started by: sharanbr
3 Replies
cron(1M) System Administration Commands cron(1M)
NAME
cron - clock daemon
SYNOPSIS
/usr/sbin/cron
DESCRIPTION
cron starts a process that executes commands at specified dates and times.
You can specify regularly scheduled commands to cron according to instructions found in crontab files in the directory
/var/spool/cron/crontabs. Users can submit their own crontab file using the crontab(1) command. Commands which are to be executed only once
can be submitted using the at(1) command.
cron only examines crontab or at command files during its own process initialization phase and when the crontab or at command is run. This
reduces the overhead of checking for new or changed files at regularly scheduled intervals.
As cron never exits, it should be executed only once. This is done routinely by way of the svc:/system/cron:default service. The file
/etc/cron.d/FIFO file is used as a lock file to prevent the execution of more than one instance of cron.
cron captures the output of the job's stdout and stderr streams, and, if it is not empty, mails the output to the user. If the job does not
produce output, no mail is sent to the user. An exception is if the job is an at(1) job and the -m option was specified when the job was
submitted.
cron and at jobs are not executed if your account is locked. Jobs and processses execute. The shadow(4) file defines which accounts are not
locked and will have their jobs and processes executed.
Setting cron Jobs Across Timezones
The timezone of the cron daemon sets the system-wide timezone for cron entries. This, in turn, is by set by default system-wide using
/etc/default/init.
If some form of daylight savings or summer/winter time is in effect, then jobs scheduled during the switchover period could be executed
once, twice, or not at all.
Setting cron Defaults
To keep a log of all actions taken by cron, you must specify CRONLOG=YES in the /etc/default/cron file. If you specify CRONLOG=NO, no log-
ging is done. Keeping the log is a user configurable option since cron usually creates huge log files.
You can specify the PATH for user cron jobs by using PATH= in /etc/default/cron. You can set the PATH for root cron jobs using SUPATH= in
/etc/default/cron. Carefully consider the security implications of setting PATH and SUPATH.
Example /etc/default/cron file:
CRONLOG=YES
PATH=/usr/bin:/usr/ucb:
This example enables logging and sets the default PATH used by non-root jobs to /usr/bin:/usr/ucb:. Root jobs continue to use
/usr/sbin:/usr/bin.
The cron log file is periodically rotated by logadm(1M).
FILES
/etc/cron.d Main cron directory
/etc/cron.d/FIFO Lock file
/etc/default/cron cron default settings file
/var/cron/log cron history information
/var/spool/cron Spool area
/etc/cron.d/queuedefs Queue description file for at, batch, and cron
/etc/logadm.conf Configuration file for logadm
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO
svcs(1), at(1), crontab(1), sh(1), logadm(1M), svcadm(1M), queuedefs(4), shadow(4), attributes(5), smf(5)
NOTES
The cron service is managed by the service management facility, smf(5), under the service identifier:
svc:/system/cron:default
Administrative actions on this service, such as enabling, disabling, or requesting restart, can be performed using svcadm(1M). The ser-
vice's status can be queried using the svcs(1) command.
DIAGNOSTICS
A history of all actions taken by cron is stored in /var/cron/log and possibly in /var/cron/olog.
SunOS 5.10 5 Aug 2004 cron(1M)
Cron Jobs not running at scheduled time