<p>In short, it's not practically possible. This <a href="https://stackoverflow.com/a/12472740/598141">S/O answer</a> is quite detailed.</p>
<blockquote>
<p>Jenkins used a <a href="https://en.m.wikipedia.org/wiki/Cron#CRON_expression" rel="nofollow noreferrer">cron
expression</a>, and
the different fields are:</p>
<pre><code>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
</code></pre>
</blockquote>
<p>cron syntax simply does not support every <code>n days</code>.</p>
<p>An impractical option wuld be to have a daily job with a <a href="https://plugins.jenkins.io/conditional-buildstep/" rel="nofollow noreferrer">Conditional BuildStep</a> to calculate if this day is n × 30 days from a given fixed day and abort if not..</p>
<p>But every 30 days doesn't really align w/calendar anyways, so is that really the intent?</p>

CC BY-SA 4.0
2020-11-01T21:21:45.897Z
I used this one: https://stackoverflow.com/questions/31536055/
Alexey Vazhnov
CC BY-SA 4.0
2020-11-01T11:07:32.153Z
2020-11-01T11:07:32.153Z
Ian W
<p>Jenkins- scheduled tab change syntax like...</p>
<p>. 30 * * * *</p>
<p>Example for understanding.... similar to cron job</p>

CC BY-SA 4.0
2020-11-03T06:25:02.300Z
Is this example to run job every 30 days?
Alexey Vazhnov
CC BY-SA 4.0
2020-11-03T02:29:07.870Z
2020-11-03T02:29:07.870Z
sreeniwl
<p>Jenkins version is 2.235.5 (I should update it to next LTS version 2.249).</p>
<p>I configured Jenkins to run a job periodically every 30 days: Build Triggers → Build periodically → Schedule:</p>
<pre><code>H 3 */30 * *
</code></pre>
<p>And now I see:</p>
<blockquote>
<p>Would last have run at Saturday, October 31, 2020 3:20:39 AM EDT; would next run at Sunday, November 1, 2020 3:20:39 AM EST.</p>
</blockquote>
<p><a href="https://i.sstatic.net/fzC5U.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/fzC5U.png" alt="Jenkins Build Triggers → Build periodically → Schedule" /></a></p>
<p>So it will be started again after 1 day, not 30 days…</p>
<p>How to run a job periodically every 30 days?</p>
<p>Update: history of Jenkins &quot;predictions&quot; for schedule above (job was created October 28):</p>
<blockquote>
<p>Would last have run at Thursday, October 1, 2020 3:20:06 AM EDT; would next run at Saturday, October 31, 2020 3:20:06 AM EDT.</p>
</blockquote>
<blockquote>
<p>Would last have run at Saturday, October 31, 2020 3:20:39 AM EDT; would next run at Sunday, November 1, 2020 3:20:39 AM EST.</p>
</blockquote>
<blockquote>
<p>Would last have run at Sunday, November 1, 2020 3:20:43 AM EST; would next run at Tuesday, December 1, 2020 3:20:43 AM EST.</p>
</blockquote>

<jenkins>
Jenkins: how to run task every 30 days
Alexey Vazhnov
# Jenkins: how to run task every 30 days

(Asked by: username_0 on 2020-10-31)

Jenkins version is 2.235.5 (I should update it to next LTS version 2.249).
I configured Jenkins to run a job periodically every 30 days: Build Triggers → Build periodically → Schedule:
H 3 */30 * *

And now I see:

Would last have run at Saturday, October 31, 2020 3:20:39 AM EDT; would next run at Sunday, November 1, 2020 3:20:39 AM EST.


So it will be started again after 1 day, not 30 days…
How to run a job periodically every 30 days?
Update: history of Jenkins "predictions" for schedule above (job was created October 28):

Would last have run at Thursday, October 1, 2020 3:20:06 AM EDT; would next run at Saturday, October 31, 2020 3:20:06 AM EDT.


Would last have run at Saturday, October 31, 2020 3:20:39 AM EDT; would next run at Sunday, November 1, 2020 3:20:39 AM EST.


Would last have run at Sunday, November 1, 2020 3:20:43 AM EST; would next run at Tuesday, December 1, 2020 3:20:43 AM EST.

**Tags:** jenkins


---

## 2 answers

### Answer by username_1 on 2020-11-01. Score: 2 | Accepted answer

In short, it's not practically possible. This S/O answer is quite detailed.

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


cron syntax simply does not support every n days.
An impractical option wuld be to have a daily job with a Conditional BuildStep to calculate if this day is n × 30 days from a given fixed day and abort if not..
But every 30 days doesn't really align w/calendar anyways, so is that really the intent?

> **Comments:**
> **username_0**: I used this one: https://stackoverflow.com/questions/31536055/  

---

### Answer by username_2 on 2020-11-03. Score: -1

Jenkins- scheduled tab change syntax like...

. 30 \* \* \* \*

Example for understanding.... similar to cron job

> **Comments:**
> **username_0**: Is this example to run job every 30 days?  

---

