cron 求助

Feb 14 10:53:01 QY-ProxyServer crond(pam_unix)[14632]: session opened for user root by (uid=0)
Feb 14 10:53:08 QY-ProxyServer crond(pam_unix)[14632]: session closed for user root
Feb 14 10:54:01 QY-ProxyServer crond(pam_unix)[14803]: session opened for user root by (uid=0)
Feb 14 10:54:08 QY-ProxyServer crond(pam_unix)[14803]: session closed for user root by (uid=0)
不知道为什么隔几秒就停了,