Originally posted by: SystemAdmin

Hi

On several AIX 5.3 LPARs the timezone is currrently set to:
TZ=NZST-12NZDT,M9.5.0/02:00,M4.1.0/03:00

Daylight savings in NZ starts on Sun 28th Sep 2008, which is the fourth Sunday. Do I need to change my TZ variable to NZST-12NZDT,M9.4.0/02:00,M4.1.0/03:00 or will AIX interpret the fifth Sunday (my current timezone setting) as the last of the month and change on the 28th?

Thanks

Originally posted by: SystemAdmin

Hi,

Yes! you need to change the TZ in your /etc/environment file. One problem, I believe, is that daemons and applications will be using the old TZ, and will require a reboot to obtain the new TZ.

Regards,

George

Originally posted by: CRM

I would suggest this is correct the way I read the manual:

In more detail, the format is TZ = local_timezone,date/time,date/time. Here date is in the form of Mm.n.d, day d(0-6) of week n (1-5, where week 5 means "the last d day in month m" and which may occur in either the fourth or the fifth week) of month m of the year. Week 1 is the first week in which the day d occurs. Day zero is Sunday. This format is compliant with POSIX 1003.1 standards for Extensions to Time Functions.
So 5 means the last Sunday of the month and will be interpreted as either a 4 or a 5 depending on the lie of the month.

I would suggest that it is therefore correct.

regards

Chris

Originally posted by: SystemAdmin

Great, thanks for your help Chris.
Cheers