Cron expression for particular date

Question

I want a cron expression that represents 6th September 2010 6:00 am

Solution 1

Original question was tagged cron so this first section applies to that. See below for an updated answer for the Quartz CronTrigger tool.

---

Most crontabs don't let you specify the year so you'll probably have to put that in the script itself (or a wrapper around the script/program).

You can do this with something like:

# Only run in 2010.
if [[ $(date +%Y) != 2010 ]] ; then
    exit
fi

The option you're looking for to run at 6am on September 6 every year is:

0 6 6 9 * your_command_goes_here
│ │ │ │ │
│ │ │ │ └─ any day of the week.
│ │ │ └─── 9th month (September).
│ │ └───── 6th day of the month.
│ └─────── 6th hour of the day.
└───────── Start of the hour (minutes = 0).

---

For the Quartz CronTrigger format, you'd be looking at something like:

0 0 6 6 9 ? 2010
│ │ │ │ │ │   │
│ │ │ │ │ │   └─ 2010 only.
│ │ │ │ │ └───── any day of the week.
│ │ │ │ └─────── 9th month (September).
│ │ │ └───────── 6th day of the month.
│ │ └─────────── 6th hour of the day.
│ └───────────── Start of the hour (minutes = 0).
└─────────────── Start of the minute (seconds = 0).

Solution 2

For one-shot jobs the 'at' command is better suited than cron.

at -f filename 06:00 09/06/2010

• Man Page
• Wikipedia Article

Solution 3

It could be only in /etc/crontab by follows:

0 6 6 9 * root test `/bin/date +%Y` == 2010 && <your command>

Comments

[Admin]

can please explain with each field

[Admin]

from quartz-scheduler.org/docs/tutorials/crontrigger.html we also need to mention hour ,minute and second

[paxdiablo]

@NewBie, CronTrigger is not cron. I've never seen a cron that allows either seconds or years to be specified. Quartz may allow that, I wouldn't know since I've never used it but, if your question is about Quartz/CronTrigger rather than the real cron, you should retag it so.

[Admin]

second field is still missing pax

[Admin]

you need to edit your answer second field is not labled properly. thanks to @org.

[paxdiablo]

@NewBie, I think it is, but it may be a cultural thing. Top of the hour, at least here in the Great Southern Land, means something-o'clock (i.e., minutes = 0). Updated description to clarify.