网络错误问题:RTNETLINK answers: File exists

错误贴上：
[root@localhost network-scripts]# systemctl restart network
Job for network.service failed because the control process exited with error code. See "systemctl status network.service" and "journalctl -xe" for details.
[root@localhost network-scripts]# systemctl status network.service
● network.service - LSB: Bring up/down networking
   Loaded: loaded (/etc/rc.d/init.d/network; bad; vendor preset: disabled)
   Active: failed (Result: exit-code) since Tue 2020-08-18 09:43:34 HKT; 11s ago
     Docs: man:systemd-sysv-generator(8)
  Process: 6278 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)
    Tasks: 1
   Memory: 11.3M
   CGroup: /system.slice/network.service
           └─856 /sbin/dhclient -1 -q -lf /var/lib/dhclient/dhclient-98230ece-15b5-4d6f-8cba-7d406604929f-enp0s3.lease -pf /var/run/dhclient-enp0s3.pid enp0...

Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain network[6278]: RTNETLINK answers: File exists
Aug 18 09:43:34 localhost.localdomain systemd[1]: network.service: control process exited, code=exited status=1
Aug 18 09:43:34 localhost.localdomain systemd[1]: Failed to start LSB: Bring up/down networking.
Aug 18 09:43:34 localhost.localdomain systemd[1]: Unit network.service entered failed state.
Aug 18 09:43:34 localhost.localdomain systemd[1]: network.service failed.
[root@localhost network-scripts]# cd /etc/udev/rules.d/70-persistent-net.rules
-bash: cd: /etc/udev/rules.d/70-persistent-net.rules: No such file or directory

开始找了不少方法，什么修改mac地址，关闭NetworkManager 都没用bash

解决办法：ifdown直接解决网络

ifdown enp0s3  //enp0s3是个人网卡名字，文件名称ifcfg-enp0s3,ifdown表示禁用该网络

//以后重启网络
systemctl restart network