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https://issues.apache.org/jira/browse/OOZIE-1805?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13990097#comment-13990097
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Robert Kanter commented on OOZIE-1805:
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{quote}Cron follows system time and automatically follows daylight saving
changes. For example if you wanted to schedule a report to be calculated and
sent to business at 9am then that should probably be 9am all year round
regardless of whether it's daylight saving or not.{quote}
That applies to cron, the command line tool found on Unix/Linux systems. The
feature added by OOZIE-1306 isn't to implement cron in Oozie, but to add more
flexible scheduling; we chose to use a cron-like syntax and it is referred to
along those lines. So, this doesn't have to be exactly like cron; even so,
there are variations among cron tools.
It sounds like what you really want here is the ability for Oozie to process in
an arbitrary timezone with those timezone's DST rules or to accept other
timezones for all user-entered dates. I think it's more confusing if we were
to add this for the cron syntax but not for anything else than to leave
everything in GMT with no DST. Adding this feature would be really great and
make things much easier for users; but doing this is probably a lot of work and
has a log of edge cases that need to be looked at carefully.
> Oozie Cron diverges from standard timezone and day behaviours
> -------------------------------------------------------------
>
> Key: OOZIE-1805
> URL: https://issues.apache.org/jira/browse/OOZIE-1805
> Project: Oozie
> Issue Type: New Feature
> Environment: CDH5
> Reporter: Hari Sekhon
>
> The addition of cron syntax in Oozie (OOZIE-1306) is a good idea but the
> implementation of the fields diverges from standard cron which seems counter
> intuitive for unix veterans.
> Taken from Cloudera's blog:
> http://blog.cloudera.com/blog/2014/04/how-to-use-cron-like-scheduling-in-apache-oozie
> 1. Executing in UTC seems like a bad idea when cron uses local time… if you
> wanted to use UTC you would do it for everything and set your servers to UTC
> timezone.
> Having to translate timezones to figure out what to enter requires more
> effort on the part of the user.
> 2. The day field offsets are wrong/needlessly different compared to ISC cron
> which is zero indexed and uses 0 or 7 for Sunday instead of starting from 1.
> These points will cause a less intuitive experience and surely some
> misconfigurations... could we realign this or would it require an upstream
> fix to the Quartz Scheduler? If the latter would it be easier to just reindex
> the days and calculate the timezone in Oozie before feeding to Quartz?
> Thanks
> Hari Sekhon
> http://www.linkedin.com/in/harisekhon
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