ERRORS

[????]

When I install kudu, the log file show errors below: Log line format: 
[IWEF]mmdd hh:mm:ss.uuuuuu threadid file:line] msg
F1223 06:43:45.232053  3003 master_main.cc:68] Check failed: _s.ok() Bad 
status: Service unavailable: Cannot initialize clock: Error reading clock. 
Clock considered unsynchronized.Can you help me?Thanks;