变更步骤的说明
对于在dba组内的用户，当其crontab计划发生时，不进行authentication，而直接执行。
变更步骤
sed -i.bak '/No PAM/aaccount sufficient pam_succeed_if.so user ingroup dba' /etc/pam.d/crond
RHEL使普通用户密码过期后crontab计划仍能正常执行
WARNING: No any other purpose,keeping reminded! So sorry to offended,if necessary, contact me and I do change what I had done to protect your privileges!