How to Run Crontab Job Every Week on Sunday

How to run crontab job every week on Sunday

Here is an explanation of the crontab format.

# 1. Entry: Minute when the process will be started [0-60]
# 2. Entry: Hour when the process will be started [0-23]
# 3. Entry: Day of the month when the process will be started [1-28/29/30/31]
# 4. Entry: Month of the year when the process will be started [1-12]
# 5. Entry: Weekday when the process will be started [0-6] [0 is Sunday]
#
# all x min = */x

So according to this your 5 8 * * 0 would run 8:05 every Sunday.

Run CRON job everyday at specific time

Cron utility is an effective way to schedule a routine background job at a specific time and/or day on an on-going basis.

Linux Crontab Format

MIN HOUR DOM MON DOW CMD

Example::Scheduling a Job For a Specific Time

The basic usage of cron is to execute a job in a specific time as shown below. This will execute the Full backup shell script (full-backup) on 10th June 08:30 AM.

Please note that the time field uses 24 hours format. So, for 8 AM use
8, and for 8 PM use 20.

30 08 10 06 * /home/yourname/full-backup

• 30 – 30th Minute
• 08 – 08 AM
• 10 – 10th Day
• 06 – 6th Month (June)
• *– Every day of the week

In your case, for 2.30PM,

30 14 * * * YOURCMD

1. 30 – 30th Minute
2. 14 – 2PM
3. *– Every day
4. *– Every month
5. *– Every day of the week

To know more about cron, visit this website.

Running a cron job at 2:30 AM everyday

crontab -e

add:

30 2 * * * /your/command

Cron Job to run on a range of days only on a particular day of week

This is the crontab format:

* * * * *
| | | | |
| | | | +---- Day of the Week   (range: 0-6, 0 standing for Sunday)
| | | +------ Month of the Year (range: 1-12)
| | +-------- Day of the Month  (range: 1-31)
| +---------- Hour              (range: 0-23)
+------------ Minute            (range: 0-59)

Ubuntu man 5 crontab says:

  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)

So, this should work for you:

0 0 2-31 * 0         /home/ubuntu/x.h
0 0 2-31 * 1-6       /home/ubuntu/y.h

I'm not sure why 7 would run on Saturday--is your system time accurate and in the right timezone?

Edit: Ah, yes, unfortunately you cannot specify both the day of the week and the day of the month. From man 5 crontab:

Note: The day of a command's execution can be specified by two fields — day of month, and day of week. If both fields are restricted (i.e., aren't *), the command will be run when either field matches the current time. For example, ``30 4 1,15 * 5'' would cause a command to be run at 4:30 am on the 1st and 15th of each month, plus every Friday. One can, however, achieve the desired result by adding a test to the command (see the last example in EXAMPLE CRON FILE below).

So, the answer is:

0 0 2-31 * *       test $(date +\%u) -eq 7 && /home/ubuntu/x.h
0 0 2-31 * *       test $(date +\%u) -ne 7 && /home/ubuntu/y.h

$(date '+%u') returns 1-7 representing Monday thru Sunday. Try echo $(date '+%u') for an example.

Crontab Day of the Week syntax

0 and 7 both stand for Sunday, you can use the one you want, so writing 0-6 or 1-7 has the same result.

Also, as suggested by @Henrik, it is possible to replace numbers by shortened name of days, such as MON, THU, etc:

0 - Sun      Sunday
1 - Mon      Monday
2 - Tue      Tuesday
3 - Wed      Wednesday
4 - Thu      Thursday
5 - Fri      Friday
6 - Sat      Saturday
7 - Sun      Sunday

Graphically, * * * * * command to be executed stands for:

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