centos7 修改ssh远程登录端口

1.selinux状态

    -查看运行状态

     #sestatus

SELinux status:                 enabled
SELinuxfs mount:                /sys/fs/selinux
SELinux root directory:         /etc/selinux
Loaded policy name:             targeted
Current mode:                   enforcing
Mode from config file:          enforcing
Policy MLS status:              enabled
Policy deny_unknown status:     allowed
Max kernel policy version:      28

        #setenforce [0/1]

    0 : 转成 permissive 宽容模式

    1 ：转成 enforcing 强制模式

    -永久开启/关闭selinux

    #vim /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
# SELINUXTYPE= can take one of three two values:
#     targeted - Targeted processes are protected,
#     minimum - Modification of targeted policy. Only selected processes are protected.
#     mls - Multi Level Security protection.
SELINUXTYPE=targeted

    SELINUX=enforcing(强制)/permissive(宽容)/disabled(关闭)

enforcing ：代表SELinux正在运行中，且已经正确开始限制 domin/type 了。

permissive ：代表SELinux正在运行中，不过仅会有警告信息并不会世纪限制 domin/type 的访问。这种模式可以用来作为SELinux的调试只用。

disabled ：关闭，SELinux并没有实际运行。

2.semanage管理工具

    #yum install policycoreutils-python

    #yum provides semanage

2.修改ssh端口

    #vim /etc/ssh/sshd_config

# If you want to change the port on a SELinux system, you have to tell
# SELinux about this change.
# semanage port -a -t ssh_port_t -p tcp #PORTNUMBER
#
#Port 22
Port 12345
#AddressFamily any
#ListenAddress 0.0.0.0
#ListenAddress ::

3.向selinux中添加ssh端口 

    #semanage port -a -t ssh_port_t -p tcp 12345

4.重启ssh服务

    #systemctl restart sshd.service