systemctl
related commands: Service, chkconfig
systemd is a system and service manager under Linux, compatible with SysV and LSB startup script. systemd features include: support for parallel tasks; while using socket-type and D-Bus activation Bus service; started on demand daemon (daemon); use of Linux cgroups monitoring process; support snapshots and system recovery; maintenance and mount points automatic mount point; precise control based on the dependencies among services.
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-enabled 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
某服务重新加载配置文件 service httpd reload systemctl reload httpd.service# systemctl #输出已激活单元
# systemctl list-units #输出已激活单元
# systemctl --failed #输出运行失败的单元
# systemctl list-unit-files #查看所有已安装服务
# systemctl start nginx #启动nginx
# systemctl stop nginx #停止nginx
# systemctl restart nginx #重启nginx
# systemctl reload nginx #重新加载nginx配置
# systemctl status nginx #输出nginx运行状态
# systemctl is-enabled nginx #检查nginx是否配置为自动启动
# systemctl enable nginx #开机自动启动nginx
# systemctl disable nginx #取消开机自动启动nginx
# systemctl help nginx #显示nginx的手册页
# systemctl daemon-reload #重新载入 systemd，扫描新的或有变动的单元
# systemctl reboot #重启
# systemctl poweroff #退出系统并停止电源
# systemctl suspend #待机
# systemctl hibernate #休眠
# systemctl hybrid-sleep #混合休眠模式（同时休眠到硬盘并待机
# systemctl isolate graphical.target #等价于telinit 3 或 telinit 5