x2升级成功后，登录时报PAM unable to dlopen(/usr/lib64/security/pam_tally2.so): /usr/lib64/security/pam_tally2.so: cannot open shared object file: No such file or directory

问题原因：
PAM包中不再提供pam_tally2.so，而是由pam_faillock.so所替代。

解决办法如下：
注释配置文件/etc/pam.d/system-auth中包含pam_tally2.so的内容，如下所示：

#auth required pam_tally2.so deny=6 unlock_time=600 > account required pam_tally2.so