[CentOS] the at command

[Keith Keller]

On 2013-01-21, Jerry Geis <geisj at pagestation.com> wrote:
> I am looking for a way to "sync" up running a command on 10 boxes at the 
> same time.

Why do you think you need to do that and make sure they run at exactly
the same second?  It seems like instead it would be better to make your
command more robust to small deviations in the time at which they are
run.

> So what mechanizim exists to run command down to the second?

No such mechanism exists that I know of.  As other posters have already
mentioned, if your problem is how to execute a command on N different
boxes at exactly the same second, the granularity of the at or cron
commands are the least of your problems.

I suspect that, unless you can demonstrate a real need for this feature,
the answers you're going to get are going to amount to "run at the top
of the minute instead".  (And if you can demonstrate a legitimate need,
the problem is not going to be solved by at or cron.)

--keith


-- 
kkeller at wombat.san-francisco.ca.us