EinsteinInIct opened a new issue, #17574: URL: https://github.com/apache/dolphinscheduler/issues/17574
### Search before asking - [x] I had searched in the [issues](https://github.com/apache/dolphinscheduler/issues?q=is%3Aissue) and found no similar issues. ### What happened ### Environment Information - **DolphinScheduler Version**: 3.1.8 - **Operating System**: Red Hat Enterprise Linux - **Database**: MySQL 5.7 - **Database Timezone**: CST - **MySQL JDBC Driver**: mysql-connector-java-8.0.20 ### Problem Description When using MySQL database with CST timezone, scheduling tasks fail during daylight saving transitions due to timezone ambiguity. The CST timezone can represent both China Standard Time (UTC+8) and Central Standard Time (UTC-6/UTC-5), causing incorrect datetime storage and task scheduling failures. ### What you expected to happen ### Expected Behavior Tasks should be scheduled and executed at the correct times regardless of daylight saving transitions. ### How to reproduce ### Steps to Reproduce 1. Set up MySQL 5.7 with CST timezone configuration 2. Deploy DolphinScheduler 3.1.8 on Red Hat Enterprise Linux without explicit timezone specification (defaults to CST) 3. Schedule tasks around daylight saving transition periods (e.g., November 2, 2025): - When scheduling tasks at 14:00 and 15:00, the `schedule_time` stored in the DS database shows as 01:00 - Tasks fail to execute at the correct time due to timezone conversion errors ### Anything else ### Root Cause Analysis The fundamental issue is the **ambiguity of CST timezone identifier**: - CST can represent **China Standard Time** (UTC+8) - CST can also represent **Central Standard Time** (UTC-6, or UTC-5 during daylight saving) - This ambiguity leads to incorrect timezone conversions when storing datetime values in the database - During daylight saving transitions, the timezone conversion becomes unpredictable, causing scheduling failures ### Actual Behavior Tasks are stored with incorrect `schedule_time` values in the database and fail to execute at the expected times during daylight saving transitions. ### Proposed Solution 1. **Configuration Fix**: Add explicit timezone configuration (Asia/Shanghai) during service startup via JVM parameters 2. **Documentation Enhancement**: Add clear timezone configuration warnings in the MySQL installation documentation ### Documentation Enhancement Request **Add prominent timezone warnings in the MySQL installation documentation section**: ### Priority High - Affects production scheduling reliability during seasonal timezone transitions ### Version 3.1.x ### Are you willing to submit PR? - [x] Yes I am willing to submit a PR! ### Code of Conduct - [x] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct) -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
