As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT NR 6421 DURING CLIMBOUT FROM CVG NR 1 ENGINE N1 VIB INCREASED TO 1.8 YELLOW, IN CRUISE VIB WENT TO 2.4 YELLOW. SHUT DOWN ENGINE, RESTARTED ENGINE AND VIB WENT AWAY. EMERGENCY DECLARED. A/C CONTINUED TO MSP AND LANDED SAFELY. INSPECTED NR 1 ENGINE FAN BLADES, NO DEFECTS NOTED. PERFORMED GROUND RUNS WITH NO DEFECTS NOTED.