1、我们安装一个httpd服务来测试一下 --now参数
yum install httpd
2、查看一下当前服务状态 可以看到服务没有启动 而且服务没有自启
[root@master1 ~]# systemctl status httpd ● httpd.service - The Apache HTTP Server Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; vendor preset: disabled) Active: inactive (dead) Docs: man:httpd(8) man:apachectl(8) [root@master1 ~]# [root@master1 ~]# systemctl is-enabled httpd disabled [root@master1 ~]#
3、用 --now参数启动一下
systemctl enable --now httpd
4、我们在看一下状态 可以看到服务启动了 同时 也开机自启了
[root@master1 conf]# systemctl status httpd.service ● httpd.service - The Apache HTTP Server Loaded: loaded (/usr/lib/systemd/system/httpd.service; enabled; vendor preset: disabled) Active: active (running) since Tue 2021-03-02 17:42:17 CST; 32s ago Docs: man:httpd(8) man:apachectl(8) Main PID: 26736 (httpd) Status: "Total requests: 0; Current requests/sec: 0; Current traffic: 0 B/sec" Tasks: 6 Memory: 2.8M CGroup: /system.slice/httpd.service ├─26736 /usr/sbin/httpd -DFOREGROUND ├─26737 /usr/sbin/httpd -DFOREGROUND ├─26738 /usr/sbin/httpd -DFOREGROUND ├─26739 /usr/sbin/httpd -DFOREGROUND ├─26740 /usr/sbin/httpd -DFOREGROUND └─26741 /usr/sbin/httpd -DFOREGROUND Mar 02 17:42:17 master1 systemd[1]: Starting The Apache HTTP Server... Mar 02 17:42:17 master1 systemd[1]: Started The Apache HTTP Server. Mar 02 17:42:17 master1 httpd[26736]: AH00558: httpd: Could not reliably determine the server's fully qualified domain name, using 192.168.1...s message Hint: Some lines were ellipsized, use -l to show in full.
[root@master1 conf]# systemctl is-enabled httpd.service enabled [root@master1 conf]#
5、同理如果用 systemctl disable --now httpd.service 去关闭服务 他会关闭服务的同时 去掉开机自启
[root@master1 conf]# systemctl disable --now httpd.service Removed symlink /etc/systemd/system/multi-user.target.wants/httpd.service. [root@master1 conf]# systemctl is-enabled httpd.service disabled [root@master1 conf]# systemctl status httpd.service ● httpd.service - The Apache HTTP Server Loaded: loaded (/usr/lib/systemd/system/httpd.service; disabled; vendor preset: disabled) Active: inactive (dead) Docs: man:httpd(8) man:apachectl(8)