Run a cron script at 1:00 PM UTC every day - cron

i need to run a cron at 1:00 PM UTC every day, is this the right crontab for UTC ?
0 1 * * *

No, it should be in 24 hour format so
0 13 * * *

The timezone within which cron jobs are scheduled by default, is based upon the default system timezone (/etc/timezone). Depending upon your distribution, you may be able to set CRON_TZ in your crontab.
If your system default timezone is UTC then 0 1 * * * is correct.
You can add a job like the following to your crontab to determine which timezone cron is using:
0 * * * * date > /tmp/date.out

Related

Need a cron expression

I am trying to get a cron expression through cron convertors online but it won't be able to do the same.
Some please help. I need a cron expression which should run every 3 hours starting at 00:10.
00:10
03:10
06:10
...
Also I need a cron expression that runs every 30 mins starting from 00:00.
00:00
00:30
01:00
...
something like this^
I tried
10/3 * * * *
and
*/30 * * * *
I need a cron expression which should run every 3 hours starting at
00:10
Simply with
10 0/3 * * * your_command
This way, the cron will run the specified command at 10 minutes past midnight (10 0) and then every 3 hours thereafter (0/3)
Also I need a cron expression that runs every 30 mins starting from
00:00
Then this might do the work
0,30 0-23/1 * * * /path/to/command
So it will run at 00:00 and 00:30 every day (0,30), every hour (0-23/1), and regardless of the day of the month, month, or day of the week (*)

Running a cron at 4 am and 4 pm

The following cron expression cron(0 14 ? * MON-FRI *) basically runs something 4:00 pm from Monday to Friday.
I am wondering if it is possible to modify the expression so I can run something at 4:00 am and 4:00 pm every Monday to Friday.
Use this crontab line to run command_name at 4:00 and 16:00 (4 AM and 4 PM) Monday-Friday:
0 4,16 * * 1-5 command_name
From crontab manual:
The time and date fields are:
field allowed values
----- --------------
minute 0-59
hour 0-23
day of month 1-31
month 1-12 (or names, see below)
day of week 0-7 (0 or 7 is Sunday, or use names)
Your Cron job description looks different from the general crontab. But to give you an idea of how to achieve what you're looking for:
Edit cron-table. Choose your editor.
crontab -e
Add 2 lines cron jobs.
* 4 * * 1-5 /usr/bin/...# Your command goes here 04:00 am.
* 16 * * 1-5 /usr/bin/...# Your command goes here 04:00 pm.
4PM (16:00): 0 16 * * MON-FRI
See crontab guru
"At 16:00 on every day-of-week from Monday through Friday.”
4AM &4 PM (4:00 & 16:00): 0 4,16 * * MON-FRI
See crontab guru
β€œAt minute 0 past hour 4 and 16 on every day-of-week from Monday through Friday.”

How to schedule the CRON to be run 1 to 1:30?

I need to know cron expression to run every monday between 1 and 1:30 am.
I have tried below expressions not worked.
1 * 1-2 ? * MON *
Can anyone help me to write cron expression?
Try the below expression
0 0-30 1 ? * MON *
Try this: 0 0-30 1 ? * MON
I think, you need at least 6 slots to fill so CRON expression is valid.

Crontab executes at the wrong time

I have a crontab settings as follows:
sudo crontab -l -u bheng
Contents:
#field allowed values
# ----- --------------
# minute 0-59
# hour 0-23
# day of month 1-31
# month 1-12 (or names, see below)
# day of week 0-7 (0 or 7 is Sun, or use names)
#
# m h dom mon dow command
MAILTO="bheng#outlook.com"
#Daily
01 22 * * * php /home/mysite.com/artisan products:exportdiff --interval="yesterday"
16 22 * * * php /home/mysite.com/artisan images:exportdiff --interval="yesterday"
31 22 * * * php /home/mysite.com/artisan publications:exportdiff --interval="yesterday"
#Weekly
1 23 * * 7 php /home/mysite.com/artisan publications:exportdiff --interval="last sunday"
16 23 * * 7 php /home/mysite.com/artisan images:exportdiff --interval="last sunday"
31 23 * * 7 php /home/mysite.com/artisan products:exportdiff --interval="last sunday"
As you can see, it suppose to be kicking at 10 and 11 PM at night.
But instead, I got 3 emails at 5 PM yesterday at 5:01 PM, 5:16 PM, 5:31 PM.
I thought it was the time wrong the in system or VM so I checked it I saw UTC time.
Then, I update it by running sudo dpkg-reconfigure tzdata and set it to US Eastern time.
Now, when I ran date command I got Ex.Thu Dec 15 07:56:27 EST 2016 correctly as US EST time.
Is there some service that I need to restart?
Or is this something other crontab settings that might have overwrite my current settings ?
I believe you have to restart cron after making time / time zone related changes.
Depending on your version of cron, you might be able to restart it with sudo service cron restart.

What is the syntax for a cron job that runs 15 and 45 minutes after the hour?

What is the syntax for a cron job that runs 15 and 45 minutes after the hour? (So every 30 minutes.)
Would the syntax be something like:
15,45,30 * * * * wget -O /dev/null http://somesite.com/4_leads.php
So for example it would run at
2:15
2:45
3:15
3:45
4:15
4:45
and so on
From man 5 crontab
field allowed values
----- --------------
minute 0-59
hour 0-23
day of month 1-31
month 1-12 (or names, see below)
day of week 0-7 (0 or 7 is Sun, or use names)
Or, in other words
# m h dom mon dow user command
15,45 * * * * yourusername wget -O /dev/null http://somesite.com/4_leads.php
Skip the username field if you place the entry in a user specific crontab, via crontab -e, crontab -e -u yourusername, or similar.
This question may be better suited to serverfault.

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