Recently my country has stopped using DST (daylight saving time) and I have some network devices that have their time zone offsets set by old values and this causes them to display the time with an error (being an hour different form the actual time in my time zone). Since it's not possible to update their time zone database, what I'm trying to do is to make chrony sync its system time with an external server and then report the time with an offset to cause those devices show the correct time. Is this possible? this question asks how to disable the DST on the server which is something I do not want to do. I want the server to have the correct time, but send the time to clients at an offset.
The devices allow you to choose time zones by name and have a predefined offset for each timezone which cannot be changed.
What is happening now is:
Server-> has the correct time and time zone
Client-> Gets time from server (UTC I'm assuming) and has the same time zone as server set on it but shows it with and hour difference
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1 Answers
No, NTP does not have the concept of time zones. Local time is a result of applying rules to UTC time.
Intentionally making NTP off by an hour or so will be more fragile and confusing than fixing the time zone. If any new hosts are introduced with clocks set to generally accepted time via internet, they will be wrong despite having the correct time zone. NTP is tuned to millisecond errors, some software will reject enormous offsets as falsetickers. Even though you can use "offset" keyword in chrony.conf to adjust arbitrary seconds to NTP servers, that doesn't mean you should. I have no examples of that being successfully used as a hack for local time.
Yes it is possible to update time zone databases.
Any computer that has a local time clock important to a human, should be getting software updates for time zones.
For some software, you have the option of going faster than your maintainer. For example, on a Linux distribution, you could build a custom tzdata package based on upstream. It is relatively self contained, and entirely based on libre plain-text data and code.
Temporarily you might do the annoying workaround of setting the time zone twice a year or whatever. Or going without offsets and people get UTC. Every civil-time clock since 1970 is included in the source data, there should be something to pick from.
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