topic Re: /etc/localtime in Operating System - Linux

/etc/localtime

Wilfred Chau_1 — Thu, 22 Mar 2007 12:17:13 GMT

Does anyone know how the localtime file is used?

I know when the system reboots, this file will be read to adjust the HW clock. But what if the system is up and running?

We have a box which a DST patch was installed but the localtime file was not updated. I am afraid the system clock will move forward next Sunday.

Re: /etc/localtime

James R. Ferguson — Thu, 22 Mar 2007 13:34:59 GMT

Hi Wilfred:

The manpages for 'hwclock' in the section titled "Clocks in a Linux System" nicely explain this.

Regards!

...JRF...

Re: /etc/localtime

Ivan Ferreira — Thu, 22 Mar 2007 14:19:12 GMT

The /etc/localtime file is a copy of the timezone file located in /usr/share/zoneinfo. When you modify the timezone to update the DST changes, the /usr/share/zoneinfo/ is updated and you should copy the file to /etc/localtime.

cp /usr/share/zoneinfo/ /etc/localtime

You can check DST rules with zdump -v

Re: /etc/localtime

Steven E. Protter — Thu, 22 Mar 2007 14:26:33 GMT

Shalom,

A possible solution to this would be to connect your system to an ntp time source. There probably is one on you network you can configure in ntp.conf

If you installed the DST patch and the system clock already moved forward its not going to do it again.

SEP

Re: /etc/localtime

Wilfred Chau_1 — Thu, 22 Mar 2007 15:39:10 GMT

thanks all.

What is the different between these 2 commands?

zdump -v US/Pacific

zdump -v /etc/localtime

Re: /etc/localtime

Ivan Ferreira — Thu, 22 Mar 2007 16:06:03 GMT

The first command will open the zone file in /usr/share/zoneinfo, the second command will open /etc/localtime, if the files are equal as it should, you should get no differences in the rules.

Re: /etc/localtime

Wilfred Chau_1 — Thu, 22 Mar 2007 16:09:45 GMT

thank you all