systemctl命令是系统服务管理器指令,它实际上将 service 和 chkconfig 这两个命令组合到一起。
|任务|旧指令|新指令|
|-|-|-|
|使某服务自动启动|chkconfig --level 3 httpd on|systemctl enable httpd.service|
|使某服务不自动启动|chkconfig --level 3 httpd off|systemctl disable httpd.service|
|检查服务状态|service httpd status|systemctl status httpd.service (服务详细信息) systemctl is-active httpd.service (仅显示是否 Active)|
|显示所有已启动的服务|chkconfig --list|systemctl list-units --type=service|
|启动某服务|service httpd start|systemctl start httpd.service|
|停止某服务|service httpd stop|systemctl stop httpd.service|
|重启某服务|service httpd restart|systemctl restart httpd.service|
#### 实例
##### 1.启动nfs服务
systemctl start nfs-server.service
##### 2.设置开机自启动
systemctl enable nfs-server.service
##### 3.停止开机自启动
systemctl disable nfs-server.service
##### 4.查看服务当前状态
systemctl status nfs-server.service
##### 5.重新启动某服务
systemctl restart nfs-server.service
##### 6.查看所有已启动的服务
systemctl list -units --type=service
开启防火墙22端口
iptables -I INPUT -p tcp --dport 22 -j accept
如果仍然有问题,就可能是SELinux导致的
关闭SElinux:
修改/etc/selinux/config文件中的SELINUX=””为disabled,然后重启。
彻底关闭防火墙:
sudo systemctl status firewalld.service
sudo systemctl stop firewalld.service
sudo systemctl disable firewalld.service