Cron expression starting at a fixed time - cron

I can't figure out how to make a cron expression that starts at 11:45 and then runs every 25 minutes every friday between 11:45 and 22:00.
This is the best i could do but i can't make it start at 11:45.
*/25 11-22 * * 5

Related

Cronjob to run after every 30 minutes from a specific time

If my cron job runs first at suppose 9:15. Then how do I make it run after every 30 minutes from then at 9:45 then 10:15 and so on?
How about:
15,45 9-23 * * *
This should give you “At minute 15 and 45 past every hour from 9 through 23.” (according to: https://crontab.guru/#15,45_9-23_*_*_*)

Run a cron job every 45 minute only between 10 am to 10 pm

I need my crontab to execute every 45 minute of hour between 10 am to 10 pm.
currently I trying this
*/45 10-21 * * *
is this right or not?
This would start the first job at 10:45am last one at 9:45pm and jobs started at 45th min of every hour in between.
You can refer here how cron works https://man7.org/linux/man-pages/man5/crontab.5.html

What's the cron expression for this?

I'm new to cron and I'm using this library. I'm trying to figure out how to write an expression which translates to
"every minute, between 10 am and 2:30 pm, Sun-Thur."
What I have so far is * 10 * * 0-4 but I'm not sure how to add the 2:30. All the examples I've seen only have minutes specified in the start, not the end.
That would be:
* 10-13 * * 0-4 command
0-30 14 * * 0-4 command
The first expression runs every minute from 10 to 14 from Sun to Thu, and the second one runs every minute from 14 to 14:30 from Sun to Thu, so basically your cron needs to be done in 2 lines.

Run CRON job everyday at specific time

Right now i am running my cron job everyday at 3.00PM
0 15 * * *
But I want to run my cron job twice in a day. 10.30AM and 2.30PM
0 30 10 * * *
I believe this command will run at 10.30AM. How should i run it in 2.30PM?
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
30 – 30th Minute
14 – 2PM
*– Every day
*– Every month
*– Every day of the week
To know more about cron, visit this website.
From cron manual http://man7.org/linux/man-pages/man5/crontab.5.html:
Lists are allowed. A list is a set of numbers (or ranges) separated
by commas. Examples: "1,2,5,9", "0-4,8-12".
So in this case it would be:
30 10,14 * * *
you can write multiple lines in case of different minutes, for example you want to run at 10:01 AM and 2:30 PM
1 10 * * * php -f /var/www/package/index.php controller function
30 14 * * * php -f /var/www/package/index.php controller function
but the following is the best solution for running cron multiple times in a day as minutes are same, you can mention hours like 10,30 .
30 10,14 * * * php -f /var/www/package/index.php controller function

Cron job run every N hours (where 24 isn't evenly divisible by N) doesn't work as expected

For example, if I have a cron job that I want to run every 9 hours:
0 */9 * * * my_script
The job is executed at 00:00, 9:00, and 18:00; and then the same hours the next day.
What I want is for the job to execute at 00:00, 9:00, 18:00; then 03:00, 12:00, 21:00 the next day -- a true "every 9 hours".
Is there any way make cron job run EVERY 9 hours?
Specifying */9 means that the job runs every 9 hours starting at 00:00. It starts again at 00:00 every day.
There is no syntax in cron to run a job every 9 hours.
What you can do is run a job every 3 hours, and have the command itself examine the current time and only execute 1 time out of 3. Or it can run every hour and execute one time out of every 9. Don't assume that the current time will be exact; it might run a few seconds after the hour.

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