I have a job with as cron:
5 3,21 * * 1-5
This will run my job at 03:05AM and 09:05PM. Now I read it's a best practice to use H.
I try:
H/5 3,21 * * 1-5
What is the meaning now? Will this schedule a build in a range of 5 minutes or 5 minutes after 3AM and 21PM?
The H will take a numeric hash of the Job name and use this to ensure that different jobs with the same cron settings do not all trigger at the same time. This is a form of Scheduling Jitter
H/5 in the first field means Every five minutes starting at some time between 0 and 4 minutes past the hour
So H/5 3,21 * * 1-5
is Every five minutes between 03:00 and 03:59 and then between 21:00 and 21:59 on Mon -> Fri but starting at some 'random' time between 03:00 and 03:04 and then the same number of minutes after 21:00
If you want to run once per hour between 03:00-03:59 and 21:00-21:59 on Mon -> Fri, you can use H 3,21 * * 1-5 where H will be replaced by some number between 0-59 depending on job name.
The user interface will tell you when the job will last have triggered and will next trigger
I am using whenever for scheduling in my rails app.
I could not find how to run my cronjobs on every tuesday and friday of the week anywhere in the gem's documentation.
This is what I am doing right now is this correct?
every [:tuesday, :friday], at: '12:00am', :roles => [:my_role] do
runner "User.notify"
end
You can use the plain crontab syntax in the schedule.rb
every '0 0 * * 2,5', :roles => [:my_role] do
runner "User.notify"
end
'0 0 * * 2,5' - “At 12:00 on Tuesday and Friday.”
It's pretty simple:
Minute Hour Day of Month Month Day of Week
(0-59) (0-23) (1-31) (1-12 or Jan-Dec) (0-6 or Sun-Sat)
0 0 * * 2,5
Refs for help 1, 2
I am trying to schedule a jenkins build with the following:
start every day between 6PM to 7AM and on Friday and Saturday run every 30 minutes... but it seems for some reason a little bit hard.
Any help will be appreciates.
So I used 2 different jobs:
first is:
H/30 * * * 5-6 - every hour at weekend (Friday and Saturday)
H/60 18,7 * * 0-5 - Every hour between 18:00 to 7:00 on working days
You can do this by checking "Build periodically" and entering the following:
# Run every thirty minutes for the 48 hours of Friday and Saturday
H/30 * * * 5-6
# Run once per hour, between 18:00 and 06:59, on Mon,Tue,Wed,Thu,Fri
H 18-6 * * 1-5
Note also that this second expression will not run from Friday 6pm until Saturday 7am — it will stop at midnight, and resume again on Monday morning between midnight and 7am.
When using the whenever gem we can set a monthly job like this :
every :month do
...
end
Will this run the job at the end of the month or at the start of the month? I want to run it at the end.
From the tests in whenever repo:
assert_equal '0 0 1 * *', parse_time(:month)
So :month will generate a cron entry that looks like 0 0 1 * *..
This corresponds to run once a month at midnight of the first day of the month.
One way to make the job run last day of the month would be to use the raw cron entry in wherever as follows:
every '0 0 L * *' do
...
end
This assumes that the cron on the server supports the L flag for representing the last day of the month.
See Cron job to run on the last day of the month for more about running a cron job on the last day of the month.
I added a new job in Jenkins, which I want to schedule periodically.
From Configure job, I am checking the "Build Periodically" checkbox and in the Schedule text field added the expression:
15 13 * * *
But it does not run at the scheduled time.
Is it the correct procedure to schedule a job?
The job should run at 4:20 AM, but it is not running.
By setting the schedule period to 15 13 * * * you tell Jenkins to schedule the build every day of every month of every year at the 15th minute of the 13th hour of the day.
Jenkins used a cron expression, and the different fields are:
MINUTES Minutes in one hour (0-59)
HOURS Hours in one day (0-23)
DAYMONTH Day in a month (1-31)
MONTH Month in a year (1-12)
DAYWEEK Day of the week (0-7) where 0 and 7 are sunday
If you want to schedule your build every 5 minutes, this will do the job : */5 * * * *
If you want to schedule your build every day at 8h00, this will do the job : 0 8 * * *
For the past few versions (2014), Jenkins have a new parameter, H (extract from the Jenkins code documentation):
To allow periodically scheduled tasks to produce even load on the system, the symbol H (for “hash”) should be used wherever possible.
For example, using 0 0 * * * for a dozen daily jobs will cause a large spike at midnight. In contrast, using H H * * * would still execute each job once a day, but not all at the same time, better using limited resources.
Note also that:
The H symbol can be thought of as a random value over a range, but it actually is a hash of the job name, not a random function, so that the value remains stable for any given project.
More example of using 'H'
The format is as follows:
MINUTE (0-59), HOUR (0-23), DAY (1-31), MONTH (1-12), DAY OF THE WEEK (0-6)
The letter H, representing the word Hash can be inserted instead of any of the values. It will calculate the parameter based on the hash code of you project name.
This is so that if you are building several projects on your build machine at the same time, let’s say midnight each day, they do not all start their build execution at the same time. Each project starts its execution at a different minute depending on its hash code.
You can also specify the value to be between numbers, i.e. H(0,30) will return the hash code of the project where the possible hashes are 0-30.
Examples:
Start build daily at 08:30 in the morning, Monday - Friday: 30 08 * * 1-5
Weekday daily build twice a day, at lunchtime 12:00 and midnight 00:00, Sunday to Thursday: 00 0,12 * * 0-4
Start build daily in the late afternoon between 4:00 p.m. - 4:59 p.m. or 16:00 -16:59 depending on the projects hash: H 16 * * 1-5
Start build at midnight: #midnight or start build at midnight, every Saturday: 59 23 * * 6
Every first of every month between 2:00 a.m. - 02:30 a.m.: H(0,30) 02 01 * *
Jenkins lets you set up multiple times, separated by line breaks.
If you need it to build daily at 7 am, along with every Sunday at 4 pm, the below works well.
H 7 * * *
H 16 * * 0
*/5 * * * * means every 5 minutes
5 * * * * means the 5th minute of every hour
The steps for scheduling jobs in Jenkins:
click on "Configure" of the job requirement
scroll down to "Build Triggers" - subtitle
Click on the checkBox of Build periodically
Add time schedule in the Schedule field, for example: #midnight
Note: under the schedule field, can see the last and the next date-time run.
Jenkins also supports predefined aliases to schedule build:
#hourly, #daily, #weekly, #monthly, #midnight
#hourly --> Build every hour at the beginning of the hour --> 0 * * * *
#daily, #midnight --> Build every day at midnight --> 0 0 * * *
#weekly --> Build every week at midnight on Sunday morning --> 0 0 * * 0
#monthly --> Build every month at midnight of the first day of the month --> 0 0 1 * *
Another example, How to run only on a specific day of the week:
# Every Sunday at 19:00
0 19 * * 0
The number at the end is the day of the week according to the following list:
0 = Sunday
1 = Monday
2 = Tuesday
3 = Wednesday
4 = Thursday
5 = Friday
6 = Saturday
If you are interested in how many days a week you can add a comma like this:
# Monday, Wednesday and Friday:
0 19 * * 1,3,5
Jenkins Job Scheduling Syntax
First, let’s look at the Jenkins job scheduling configuration. It looks a lot like Linux’s cron syntax, but you don’t have to be familiar with command line Linux to figure it out.
A scheduling entry consists of five whitespace-separated fields. You can schedule a job for more than one time by adding more than one entry.
Screenshot
Each field can contain an exact value or use a set of special expressions:
The familiar asterisk * indicates all valid values. So, a job that runs every day has a * in the third field.
A dash separates ranges of values. For example, a job that runs every hour from 9:00 a.m. to 5:00 p.m. would have 9-17 in the second field.
Intervals are specified with a slash /. A job that runs every 15 minutes has H/15 in the first field. Note that the H in the first field has a special meaning. If you wanted a job to run every 15 minutes, you could configure it as 0/15, which would make it run at the start of every hour. However, if you configure too many jobs this way, you can overload your Jenkins controller. Ultimately, the H tells Jenkins to pick a minute based on a hash of the job name.
Finally, you can specify multiple values with a comma. So, a job that runs Monday, Wednesday, and Friday would have 1,3,5 in the fifth field.
Jenkins provides a few examples in their help section for scheduling.
Every fifteen minutes (perhaps at :07, :22, :37, :52):
H/15 * * * *
Every ten minutes in the first half of every hour (three times,
perhaps at :04, :14, :24):
H(0-29)/10 * * * *
Once every two hours at 45 minutes past the hour starting at 9:45 AM
and finishing at 3:45 PM every weekday:
45 9-16/2 * * 1-5
Once in every two hour slot between 8 AM and 4 PM every weekday
(perhaps at 9:38 AM, 11:38 AM, 1:38 PM, 3:38 PM):
H H(8-15)/2 * * 1-5
Once a day on the 1st and 15th of every month except December:
H H 1,15 1-11 *
Jenkins also has a set of aliases that makes using common intervals easier.
Screenshot of table
To schedule a cron job every 5 minutes, you need to define the cron settings like this:
*/5 * * * *
Try this.
20 4 * * *
Check the below Screenshot
Referred URL - https://www.lenar.io/jenkins-schedule-build-periodically/
Try using 0 8 * * *. It should work
Jenkins uses Cron format on scheduling.
You can refer this link for more detailhttps://en.wikipedia.org/wiki/Cron.
One more thing, Jenkins provide us a very useful preview. Please take a look on the screenshot.
I hope this help. Thanks