A.crond B.atd C.atrun D.crontab
A.~/.ssh/known_keys B.~/.ssh/allowed_keys C.~/.ssh/authorized_keys D.~/.ssh/trusted_keys
A.在/etc/group文件中,添加sales:44:user1,user2,user3 B.使用命令groupaddsales C.使用命令groupadd-asalesuser1user2user3 D.在/etc/group文件中,添加sales::44:user1,user2,user3