UNIX Scheduling with cron

scottalanmiller

@JaredBusch said in UNIX Scheduling with cron:

Thanks,
I always have to look this up again because i never do it often enough to have ti 100% in memory.

Definitely check it out and let me know if anything is unclear or missing. Cron is always just a little confusing and I wanted to balance making it easy but having the needed info.

JaredBusch

@scottalanmiller said in UNIX Scheduling with cron:

The fields can be in these forms:

Single Number: 5

List of Numbers: 0,15,30,45

Range of Numbers: 1-5

All: *

From memory here, not bothering to check Google at the moment, but can you not also mix a list and range?

0,8-17,22

So that would send at midnight, and every hour 8-17 and then 22?

stacksofplates

Just to point out, there are some other strings you can use also.

@yearly
@weekly
@daily

You can also use /

0-30/5 * * * *

Is every 5 minutes for the first 30 minutes.

scottalanmiller

@JaredBusch said in UNIX Scheduling with cron:

@scottalanmiller said in UNIX Scheduling with cron:

The fields can be in these forms:

Single Number: 5

List of Numbers: 0,15,30,45

Range of Numbers: 1-5

All: *

From memory here, not bothering to check Google at the moment, but can you not also mix a list and range?
0,8-17,22
So that would send at midnight, and every hour 8-17 and then 22?

Yes, I'm pretty sure that that is correct.

tonyshowoff

I've been dealing with cron for... 22 years I guess, and it still irritates the hell out of me. Anyway, great work.

coliver

@johnhooks said in UNIX Scheduling with cron:

Just to point out, there are some other strings you can use also.
@yearly
@weekly
@daily
You can also use /
0-30/5 * * * *
Is every 5 minutes for the first 30 minutes.

I didn't know about the '/' That's really good to know.

scottalanmiller

@tonyshowoff said in UNIX Scheduling with cron:

I've been dealing with cron for... 22 years I guess, and it still irritates the hell out of me. Anyway, great work.

Thanks.

scottalanmiller

@coliver said in UNIX Scheduling with cron:

I didn't know about the '/' That's really good to know.

I tacked it on in the advanced section at the end. This one I've seen used in real life. Never seen anyone use @monthly, for example. I know that it exists, but just have never seen it get used.

tonyshowoff

@scottalanmiller said in UNIX Scheduling with cron:

@coliver said in UNIX Scheduling with cron:

I didn't know about the '/' That's really good to know.

I tacked it on in the advanced section at the end. This one I've seen used in real life. Never seen anyone use @monthly, for example. I know that it exists, but just have never seen it get used.

I do, for expiring old user sessions.

travisdh1

I was going to say that it's another handy reference to the time formatting for cron, but I normally just use the man page.

Alex Sage

6:03 AM

03 6 * * * <command>

or

3 6 * * * <command>

???

JaredBusch

@aaronstuder said in UNIX Scheduling with cron:

6:03 AM

03 6 * * * <command>

or

3 6 * * * <command>

???

The latter.

Alex Sage

Thanks!