My region is planning to stop switching between standard time and daylight time in November and remain on daylight time year-round. Since this CentOS installation is already end-of-life, can I manually configure a fixed UTC offset, or otherwise update its timezone data so the system uses the new local-time rules?
3 Answers
If you truly want a fixed offset rather than regional timezone rules, configure the system and applications to use an appropriate fixed-offset timezone such as an Etc/GMT zone. Be careful with the sign convention for Etc/GMT names, and understand that a fixed offset will not automatically follow future legal changes or historical timezone transitions.
The cleanest long-term solution is to migrate to a supported operating system. An end-of-life release has security risks and will not reliably receive timezone updates. If migration is not immediately possible, install a newer tzdata package from a trusted source or backport it yourself.
You can obtain newer timezone data from the upstream timezone database and install or package it locally. It is usually safer to build a replacement package with a version newer than the old system package, while making sure it will not conflict with future vendor packages. Check all applications separately, because Java/OpenJDK and some databases may carry their own timezone files instead of using the operating system's copy.

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