[mythtv-users] US MythTV users: will your recordings be 1 hour off on March 11th?

Ross Campbell ross.campbell at gmail.com
Tue Jan 16 21:36:09 UTC 2007

For those who don't know or forgot, daylight savings time rules change
in most parts of the US this year... DST will start 3 weeks earlier
and end 1 week later thanks to the brilliant minds behind the Energy
Policy act of 2005 -

So what?!

Well, your NTP time sync keeps your system time correct, but your
TIMEZONE is locally interpreted, so anyone with old/custom/unsupported
Linux distros risks having their mythtv recordings off by ONE HOUR for
the duration of the timezone change periods (4 weeks out of the year).
That's probably not what you want... and the change starts March 11th
this year - less than two months from now.

If you run an OLD distro that doesn't have updated timezone rules, you
may want to do some research about if there is an updated 'tzdata'
source package you can install.

For FC/redhat/EL distributions, 'rpm -q tzdata' will tell you the
version installed.
I believe anything newer than about tzdata-2005m will add the
appropriate changes needed to ensure that your recordings don't miss a

You may have luck building a newer tzdata src rpm from here:

Or... you may be able to copy the tzdata binary files for US timezones
from a newer Linux/UNIX distribution (?) - I don't know much about the
tzdata binary format... is it compiled or endian or just a common
binary blob?


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