I was doing timezone and DST testing which is required for some of my products
Here is the strange behaviour i observed
First i did set the timezone to PST 2010 (which is less than GMT basically negative timezone)
zdump -v /etc/localtime |grep 2010
/etc/localtime Sun Mar 14 09:59:59 2010 UTC = Sun Mar 14 01:59:59 2010 PST isdst=0 gmtoff=-28800
/etc/localtime Sun Mar 14 10:00:00 2010 UTC = Sun Mar 14 03:00:00 2010 PDT isdst=1 gmtoff=-25200
/etc/localtime Sun Nov 7 08:59:59 2010 UTC = Sun Nov 7 01:59:59 2010 PDT isdst=1 gmtoff=-25200
/etc/localtime Sun Nov 7 09:00:00 2010 UTC = Sun Nov 7 01:00:00 2010 PST isdst=0 gmtoff=-28800
DST starts here and works fine
--------------------------------
[rootlocalhost /]# date
Sun Mar 14 01:59:58 PST 2010
[rootlocalhost /]# date
Sun Mar 14 01:59:59 PST 2010
[rootlocalhost /]# date
Sun Mar 14 03:00:00 PDT 2010
[rootlocalhost /]#
DST end here works fine
-----------------------------
Sun Nov 7 01:59:58 PDT 2010
[rootlocalhost /]# date
Sun Nov 7 01:59:58 PDT 2010
[rootlocalhost /]# date
Sun Nov 7 01:59:59 PDT 2010
[rootlocalhost /]# date
Sun Nov 7 01:00:00 PST 2010
[rootlocalhost /]# date
Sun Nov 7 01:00:00 PST 2010
When it connes to positive timezon like paris(which is GMT+1)
zdump -v /etc/localtime |grep 2010
/etc/localtime Sun Mar 28 00:59:59 2010 UTC = Sun Mar 28 01:59:59 2010 CET isdst=0 gmtoff=3600
/etc/localtime Sun Mar 28 01:00:00 2010 UTC = Sun Mar 28 03:00:00 2010 CEST isdst=1 gmtoff=7200
/etc/localtime Sun Oct 31 00:59:59 2010 UTC = Sun Oct 31 02:59:59 2010 CEST isdst=1 gmtoff=7200
/etc/localtime Sun Oct 31 01:00:00 2010 UTC = Sun Oct 31 02:00:00 2010 CET isdst=0 gmtoff=3600
DST starts here and works fine
------------------------------
[rootlocalhost /]# date
Sun Mar 28 01:59:58 CET 2010
[rootlocalhost /]# date
Sun Mar 28 01:59:59 CET 2010
[rootlocalhost /]# date
Sun Mar 28 01:59:59 CET 2010
[rootlocalhost /]# date
Sun Mar 28 03:00:00 CEST 2010
[rootlocalhost /]#
DST ends here and doesn't reset back
------------------------------------
Sun Oct 31 02:59:57 CET 2010
[rootlocalhost /]# date
Sun Oct 31 02:59:59 CET 2010
[rootlocalhost]# date
Sun Oct 31 03:00:00 CET 2010
Note:in the above case when i did set time to 2:59:55 and said ok by then CEST became CET already. That could be the reason why DST is not happening.
I tried with few other positive and negative timezone configuration all the negative time zones resets back properly where as all the positive timezones doesn't
All my timezone files are up to date,i am using fedora 9
Can any one help me regarding this ...thanks a ton in advance