Red hat Linux + TIME ZONE CONFIGURATION + details from clock file

In order to configure the Time Zone on red hat Linux machine ( version 5 and 6 ) need to configure the file:

/etc/sysconfig/clock

And create a symbolic link between

/etc/localtime to /usr/share/zoneinfo/America/New_York

but /etc/sysconfig/clock also required to set the ZONE variable as the following example:

ZONE="America/New_York"

So what is the need to set the variable ZONE=America/New_York when it is very clear from the link /etc/localtime that is pointed to /usr/share/zoneinfo/**America/New_York** ?

So what is the need to set the ZONE parameter with "America/New_York" value ?

Solution 1:

So the "correct" way to set the clock (at least prior to RHEL 7) is to edit /etc/sysconfig/clock and then run tzdata-update which will then update /etc/localtime; you've just done that step manually.

Solution 2:

With the introduction of RHEL 7 the timezone is managed through systemd, which provides a custom utility to change the timezone: timedatectl

To list all available time zones:

timedatectl list-timezones

To actually change the time zone, (as root or using sudo):

timedatectl set-timezone time_zone

timedatectl set-timezone will not only make the modified time zone take effect immediately, but will also update the /etc/localtime symlink to make that change persistent across reboots.