topic Re: Setting date backwards on HP in Operating System - HP-UX

Setting date backwards on HP

Alpa Shah — Thu, 20 Sep 2007 07:15:08 GMT

Hi,

While setting the system date backwards on HP m/c it asks me a question.

do you really want to run time backwards?[yes/no]

Is there any switch which can skip this question and change the system date?

I want to use *date* command in perl script and hence want to avoid this question.

Thanks in advance.

Re: Setting date backwards on HP

Pete Randall — Thu, 20 Sep 2007 07:31:57 GMT

The reason the question is asked is because setting the date backwards can have bad consequences for Database servers, where it messes up the re-do logs, causing recovery efforts to be problematic at best.

This little shell script snippet should get you past the response requirement:

echo "yes" > /tmp/yes_time
CTIME=`date +%m%d%H%M%y`
date $CTIME < /tmp/yes_time

Pete

Re: Setting date backwards on HP

spex — Thu, 20 Sep 2007 07:36:38 GMT

# date
Thu Sep 20 08:32:43 EDT 2007
# echo "yes" | date 09200732
date: do you really want to run time backwards?[yes/no]Thu Sep 20 07:32:00 EDT 2007
# date
Thu Sep 20 07:32:02 EDT 2007

PCS

Re: Setting date backwards on HP

Alpa Shah — Thu, 20 Sep 2007 07:41:46 GMT

Thanks a lot.

Re: Setting date backwards on HP

Ivan Krastev — Thu, 20 Sep 2007 07:46:29 GMT

Note that warning from date manual:
The cron daemon should be killed prior to setting the date backwards, then restarted.

regards,
ivan

Re: Setting date backwards on HP

Dennis Handly — Fri, 21 Sep 2007 00:47:34 GMT

I don't think anyone asked why you wanted to set the date backwards. Is this to test DST testing? If so, there are perl scripts to find the beginning and ending times after you install a tztab(4) patch.
See Clay's perl script here:
http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1097748

Re: Setting date backwards on HP

Alpa Shah — Fri, 21 Sep 2007 01:00:26 GMT

No, this is something related to licensing.
I want to install a demo license and then want to expire that license by advancing the system date for testing purpose. And then have to set the date back to current date.

Thanks much for the information.

Re: Setting date backwards on HP

Bill Hassell — Fri, 21 Sep 2007 06:48:17 GMT

Setting the date forward and backward for testing should be fine as long as the system has no production applications. But if you have any applications and cron jobs on your system, you can safely assume that there will be a lot of problems, some of which may not be immediately visible.