DST, daylight saving time (also summertime), is the practise of changing the clock at the beginning of spring and autumn. If a computer is running with the timezone set to DST the switch to and from might affect running of cron, at and other scheduled jobs. Use this tag for [clock] related questions that are specific to the switching to/and from DST or the effect of DST on programs.
Questions tagged [dst]
11 questions
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Does crond handles summer time +1 hour change?
Last weekend we had to change the time from 02:00 to 03:00.
Question: What would happen if there was a cronjob at 02:30?
crond is a very old solution for scheduling, it should probably handle it, but don't know how.
LoukiosValentine79
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How to disable DST changes for a timezone?
My system timezone is Asia/Tehran, and it has DST changes adjusts in Summer (spring forward) and fall back in Winter; however I do need to disable these DST adjustments and keep timezone always in UTC+3:30. how do I do that in Linux?
αғsнιη
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logfiles and daylight savings time
How do Linux logfiles handle daylight savings time? When you fall back not only would you get out of order values but also possibly duplicate values.
I'm thinking that I should set the system time to UTC and then process the logfiles into local…
dpetican
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How to backup DST config before applying new update?
to check "Daylight Saving Time" config for a time zone we can use this command: zdump -v
However sometimes the policy of a country changes. new updates can be downloaded
and be applied by this command: zic
For Example (This is…
BlackCrystal
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Does Debian automatically update Daylight Savings Time, even if there is no NTP server available?
I would like to know more about how DST works in Debian (and probably Debian-based distros).
Imagine the following: A computer running the newest version of debian is using the timezone Europe/Zurich. Daylight savings time will start on 2018-03-25…
dislick
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hwclock's output is effected by DST when entering it, but not when leaving it
I set system time and RTC to the following values.
date -s 2021.08.30-09:59:30 >/dev/null 2>/dev/null //set system time
hwclock -w //sync RTC to system time
Also, /etc/TZ (which is the same file as /etc/localtime in busybox) is saved…
Andy Lin
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centos: update tzdata for new DST rules in Brazil.
Brazil looks like being changing its DST rules again (next transition date was initially oct'20th, changed to nov'4th and now to nov'18th ).
Looking at ftp://ftp.iana.org/tz the last update is 2018e, which doesn't include this last change.
Any…
tonioc
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Linux DST confusion
My question is about Daylight Savings Time (DST), and whether or not the following is behaviour is normal under Linux. I am using the POSIX TZ variable to specify the timezone.
Using the example from this man page, I set the TZ variable as…
Andy J
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How to change DST start and end dates for a timezone in Red Hat Enterprise Linux and Oracle Linux?
DST start and end dates keep changing over the years for different timezones. For example, I found below link where DST start and end dates are provided for EST for different years. https://www.timeanddate.com/time/zone/usa/new-york?year=1963 In…
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How to check if DST (Daylight Saving Time) is inactive in CentOS different versions?
I have few servers with CentOS 7 and 6 as OS. Previously, the time was changed twice a year for DST and the OS automatically did this on each server.
now suddenly a law has been passed that changed the policy of daylight saving time. I wanted to…
BlackCrystal
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How to find who invoked a program?
I'm dealing with daylight saving time and found something interesting.
Assuming that the time is now 2:00 p.m., daylight saving time will start at 3:00 p.m., with an offset of +1 hour.
After 3:00 p.m., hwlock will show the time info which is added…
Andy Lin
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