Daylight savings time / 6.1 and 4.11

Josef Grosch jgrosch at
Fri Jan 19 00:26:59 UTC 2007

On Tue, Jan 16, 2007 at 01:31:22PM -0700, hal wrote:
> This came down from above?!
> Beginning in 2007, Daylight Savings Time will be lengthened one month  
> by starting three weeks earlier (2AM on the second Sunday in March)  
> and ending one week later (2AM on the first Sunday in November).
> What patch levels do I need to be at for my 4.7 and 6.1 systems to be
> daylight savings 2007 ready?
> Currently: 4.11-RELEASE-p25
> Currently: 6.1-RELEASE-p10
> hal

This is an issue here at work. We have very many FreeBSD 4.x machines and a
growing number of FreeBSD 6.x. The change when daylight saving time starts
and ends is an issue for machines in the United States and, we think,
those in Canada. The way to check if your zone file is correct is to do

    zdump -v /etc/localtime | more

Look for the following

    /etc/localtime  Sun Mar 11 09:59:59 2007 UTC = Sun Mar 11 01:59:59 2007 PST isdst=0 gmtoff=-28800
    /etc/localtime  Sun Mar 11 10:00:00 2007 UTC = Sun Mar 11 03:00:00 2007 PDT isdst=1 gmtoff=-25200
    /etc/localtime  Sun Nov  4 08:59:59 2007 UTC = Sun Nov  4 01:59:59 2007 PDT isdst=1 gmtoff=-25200
    /etc/localtime  Sun Nov  4 09:00:00 2007 UTC = Sun Nov  4 01:00:00 2007 PST isdst=0 gmtoff=-28800

If you see this, your zone file will handle the change correctly. The 6.x
series has the corrected zone files. 4.x does not have this. The best way
to handle this is to copy the zone file from /usr/share/zoneinfo on a 6.x
machine to your 4.x. 


FreeBSD 6.2         | Supreme executive power derives from a mandate 
Josef Grosch        | from the masses, not from some farcical aquatic 
jgrosch at | ceremony.

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