How to prepare older Linux systems for 2007 DST change


Daylight Saving Time In the United States 1990 Through 2015

Year DST Begins 2 a.m.
(First Sunday in April)
DST Ends 2 a.m.
(Last Sunday in October)
1990 April 1 October 28
1991 April 7 October 27
1992 April 5 October 25
1993 April 4 October 31
1994 April 3 October 30
1995 April 2 October 29
1996 April 7 October 27
1997 April 6 October 26
1998 April 5 October 25
1999 April 4 October 31
2000 April 2 October 29
2001 April 1 October 28
2002 April 7 October 27
2003 April 6 October 26
2004 April 4 October 31
2005 April 3 October 30
2006 April 2 October 29
DST Start and End date changes beginning March 2007
Year DST Begins 2 a.m.
(Second Sunday in March)
DST Ends 2 a.m.
(First Sunday in November)
2007 March 11 November 4
2008 March 9 November 2
2009 March 8 November 1
2010 March 14 November 7
2011 March 13 November 6
2012 March 11 November 4
2013 March 10 November 3
2014 March 9 November 2
2015 March 8 November 1

Daylight Saving Time updates to Linux operating systems for year 2007

Red Hat updates are available for the following current releases:
Affected Products:   

   Red Hat Desktop (v. 3)
   Red Hat Desktop (v. 4)
   Red Hat Enterprise Linux AS (v. 3)
   Red Hat Enterprise Linux AS (v. 4)
   Red Hat Enterprise Linux ES (v. 3)
   Red Hat Enterprise Linux ES (v. 4)
   Red Hat Enterprise Linux WS (v. 3)
   Red Hat Enterprise Linux WS (v. 4)

This involves an update to:

RHEL 2.1 -> glibc of at least level glibc-2.2.4-32.23

RHEL 3 & 4 -> tzdata of at least level tzdata-2006m-1.EL3 or tzdata-2006m-1.EL4 respectively.

To prepare older Linux systems for 2007 DST change:

1) Download and install the latest tzdata rpm:

# rpm -u tzdata-2006m-3.el4.noarch.rpm

2) In order for the change to be effective, you need to copy over the /etc/localtime

# zdump -v /etc/localtime | grep 2007
/etc/localtime Sun Apr 1 06:59:59 2007 UTC = Sun Apr 1 01:59:59 2007 EST isdst=0 gmtoff=-18000
/etc/localtime Sun Apr 1 07:00:00 2007 UTC = Sun Apr 1 03:00:00 2007 EDT isdst=1 gmtoff=-14400
/etc/localtime Sun Oct 28 05:59:59 2007 UTC = Sun Oct 28 01:59:59 2007 EDT isdst=1 gmtoff=-14400
/etc/localtime Sun Oct 28 06:00:00 2007 UTC = Sun Oct 28 01:00:00 2007 EST isdst=0 gmtoff=-18000

# cp /usr/share/zoneinfo/America/New_York /etc/localtime

# zdump -v /etc/localtime | grep 2007
/etc/localtime Sun Mar 11 06:59:59 2007 UTC = Sun Mar 11 01:59:59 2007 EST isdst=0 gmtoff=-18000
/etc/localtime Sun Mar 11 07:00:00 2007 UTC = Sun Mar 11 03:00:00 2007 EDT isdst=1 gmtoff=-14400
/etc/localtime Sun Nov 4 05:59:59 2007 UTC = Sun Nov 4 01:59:59 2007 EDT isdst=1 gmtoff=-14400
/etc/localtime Sun Nov 4 06:00:00 2007 UTC = Sun Nov 4 01:00:00 2007 EST isdst=0 gmtoff=-18000

Also search you system for any application have their own copy of localtime and update those if needed:
# find / -name localtime -ls

OR

To be safe, simply reboot your server and this will ensure all applications will use the DST changes.
#rpm -u tzdata-2006m-3.el4.noarch.rpm; reboot

To verify if your server will be ready for the new DST time changes in 2007
# zdump -v EST5EDT | grep 2007
# zdump -v CST6CDT | grep 2007

Advertisements

3 comments on “How to prepare older Linux systems for 2007 DST change

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s