Improvement of reliability for the precise time service systembased on GNSS CV

 LIN Si-jia^1,2,3, WANG Yu-lin¹, WANG Ping-li^1,3, LU Jian-fu^1,2,3, LIU Biao^1,2,3

1. National Time Service Center, Chinese Academy of Sciences, Xi′an 710600, China;

2. Key Laboratory of Time and Frequency Primary Standards, National Time Service Center,

Chinese Academy of Sciences, Xi′an 710600, China;

3. Graduate University of Chinese Academy of Sciences, Beijing 100039, China

Abstract: A design of double hot standby project for server system is proposed for improving the reliability of the precise time service system of NTSC based on GNSS CV. The primary-standby working mode of double hot standby servers, including the data backup and the monitoring and switching of running state of servers, is described. According to different types of data and different backup requirements, different backup policies and backup processes are adopted to realize the data backup between the primary server and the standby. The control procedures of monitoring and switching of running state for primary and standby servers are designed. The tests show that the reliability of the system is enhanced obviously.

Key words: GNSS CV; precise time; double hot standby technique; data backup