messages every 5 minutes on /var/log/messages

[mcclnx mcc]

Jul 13 08:45:02 MCG-ORA06 crond(pam_unix)[11903]:
session closed for user root
Jul 13 08:50:01 MCG-ORA06 crond(pam_unix)[11907]:
session opened for user root by (uid=0)
Jul 13 08:50:01 MCG-ORA06 crond(pam_unix)[11908]:
session opened for user root by (uid=0)
Jul 13 08:50:01 MCG-ORA06 crond(pam_unix)[11907]:
session closed for user root
Jul 13 08:50:01 MCG-ORA06 crond(pam_unix)[11908]:
session closed for user root
Jul 13 08:55:01 MCG-ORA06 crond(pam_unix)[11912]:
session opened for user root by (uid=0)
Jul 13 08:55:01 MCG-ORA06 crond(pam_unix)[11912]:
session closed for user root
Jul 13 09:00:01 MCG-ORA06 crond(pam_unix)[11914]:
session opened for user root by (uid=0)
Jul 13 09:00:01 MCG-ORA06 crond(pam_unix)[11915]:
session opened for user root by (uid=0)
Jul 13 09:00:01 MCG-ORA06 crond(pam_unix)[11914]:
session closed for user root
Jul 13 09:00:02 MCG-ORA06 crond(pam_unix)[11915]:
session closed for user root

___________________________________________________ 
 最新版 Yahoo!奇摩即時通訊 7.0，免費網路電話任你打！ 
 http://messenger.yahoo.com.tw/