1）硬盘分区

mbr 分区， 最多4个主分区/扩展分区, 原因是写在磁盘mbr扇区的  447-510 共64个字节。
gpt 分区， 最多128个分区

2）selinux 
[root@localhost ~]#cat  /etc/selinux/config 
# This file controls the state of SELinux on the system.
# SELINUX= can take one of these three values:
#     enforcing - SELinux security policy is enforced.
#     permissive - SELinux prints warnings instead of enforcing.
#     disabled - No SELinux policy is loaded.
SELINUX=enforcing

## 查看selinux状态
sestatus 

setenforce  1      ## selinux 模式设置为enforcing
setenforce  0      ## selinux 模式设置为permissive