今天在CentOS7.4下www用户下执行crontab -e 时出现报错信息，通过查看crontab的日志信息如下，无法使用pam授权用户（身份验证令牌不再有效；需要新的令牌）。
查看crontab日志信息
tail -f /var/log/cron
日志报错信息如下：
Oct 24 09:10:01 iz2ze6rdks1akg4xed25ngz CROND[16489]: (root) CMD (/usr/lib64/sa/sa1 1 1)
Oct 24 09:11:01 iz2ze6rdks1akg4xed25ngz crond[16566]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:11:01 iz2ze6rdks1akg4xed25ngz crond[16566]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:12:01 iz2ze6rdks1akg4xed25ngz crond[16658]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:12:01 iz2ze6rdks1akg4xed25ngz crond[16658]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:13:01 iz2ze6rdks1akg4xed25ngz crond[16726]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:13:01 iz2ze6rdks1akg4xed25ngz crond[16726]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:14:01 iz2ze6rdks1akg4xed25ngz crond[16793]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:14:01 iz2ze6rdks1akg4xed25ngz crond[16793]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:15:01 iz2ze6rdks1akg4xed25ngz crond[16865]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:15:01 iz2ze6rdks1akg4xed25ngz crond[16865]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:16:01 iz2ze6rdks1akg4xed25ngz crond[16939]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:16:01 iz2ze6rdks1akg4xed25ngz crond[16939]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:17:01 iz2ze6rdks1akg4xed25ngz crond[17007]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:17:01 iz2ze6rdks1akg4xed25ngz crond[17007]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:18:01 iz2ze6rdks1akg4xed25ngz crond[17071]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:18:01 iz2ze6rdks1akg4xed25ngz crond[17071]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:19:01 iz2ze6rdks1akg4xed25ngz crond[17139]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:19:01 iz2ze6rdks1akg4xed25ngz crond[17139]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
Oct 24 09:20:01 iz2ze6rdks1akg4xed25ngz crond[17210]: (www) PAM ERROR (Authentication token is no longer valid; new one required)
Oct 24 09:20:01 iz2ze6rdks1akg4xed25ngz crond[17210]: (www) FAILED to authorize user with PAM (Authentication token is no longer valid; new one required)
查看www用户密码有效期
chage -l www
[root@iz2ze6rdks1akg4xed25ngz /]# chage -l www
Last password change : Jul 24, 2019
Password expires : Oct 22, 2020
Password inactive : never
Account expires : never
Minimum number of days between password change : 7
Maximum number of days between password change : 90
Number of days of warning before password expires : 7
由此可见www用户的密码已过期，原密码有效期是90天，导致crontab命令出现执行报错的问题，调整www密码有效期就可以了，一劳永逸的方法是把www密码有效期改为永久，其中99999代表永久，使用如下命令：
chage -M 99999 www
查看www密码有效期已经改为永久了，现在crontab命令就可以正常使用了。
[root@iz2ze6rdks1akg4xed25ngz /]# chage -l www
Last password change : Jul 25, 2019
Password expires : never
Password inactive : never
Account expires : never
Minimum number of days between password change : 7
Maximum number of days between password change : 99999
Number of days of warning before password expires : 7