Each section covers the upgrade from the previous LTS release, the section on 2.387.1 covers the upgrade from 2.375.4.
Support for log rotation via SIGALRM has been removed.
The command-line argument --daemon has been removed.
Users of the official Jenkins OS packages, which rely on the copytruncate option, are not affected.
Users of the --logfile argument who have their own logrotate configuration should ensure they are using the copytruncate option rather than relying on SIGALRM.
Periodic task log files are now rotated based on the file size, with a default size of 10 MB.
Previously, they were not rotated based on the file size.
To revert to the previous behavior and disable the file size rotation, the system properties hudson.model.AsyncAperiodicWork.logRotateSize=-1 and hudson.model.AsyncPeriodicWork.logRotateSize=-1 can be used.
The minimum required Remoting version has been increased to 4.7, which released on February 16, 2021.
When an agent with a Remoting version older than 4.7 connects to the Jenkins controller, the agent connection is rejected.
Ensure that all agents are running a recent version of Remoting prior to upgrading.
Agents with unsupported Remoting versions can be allowed to connect to the controller by setting the hudson.slaves.SlaveComputer.allowUnsupportedRemotingVersions system property to true.