hi!
in fact systemd recognizes jenkins as a legacy service when trying to enable it ... (this step is missing in the documentation):
# systemctl enable jenkins
jenkins.service is not a native service, redirecting to systemd-sysv-install.
Executing: /usr/lib/systemd/systemd-sysv-install enable jenkins
Failed to execute /usr/lib/systemd/systemd-sysv-install: No such file or directory
systemd-sysv-install is part of package chkconfig, so after executing ...
# dnf install chkconfig
# systemctl enable jenkins
# systemctl start jenkins
... it works!
thx!
regards
-h