[root@testbig04 ~]# 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 Wed 2019-09-04 17:46:41 CST; 4s ago
Docs: man:systemd-sysv-generator(8)
Process: 5539 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service: control process exited, code=exited status=1
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Failed to start LSB: Bring up/down networking.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Unit network.service entered failed state.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service failed.
[root@testbig04 ~]# service NetworkManager stop
Redirecting to /bin/systemctl stop NetworkManager.service
[root@testbig04 ~]# chkconfig NetworkManager off
Note: Forwarding request to 'systemctl disable NetworkManager.service'.
Removed symlink /etc/systemd/system/multi-user.target.wants/NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.NetworkManager.service.
Removed symlink /etc/systemd/system/dbus-org.freedesktop.nm-dispatcher.service.
Removed symlink /etc/systemd/system/network-online.target.wants/NetworkManager-wait-online.service.
[root@testbig04 ~]# 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 Wed 2019-09-04 17:46:41 CST; 40s ago
Docs: man:systemd-sysv-generator(8)
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service: control process exited, code=exited status=1
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Failed to start LSB: Bring up/down networking.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Unit network.service entered failed state.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service failed.
[root@testbig04 ~]# 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 Wed 2019-09-04 17:46:41 CST; 49s ago
Docs: man:systemd-sysv-generator(8)
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com network[5539]: RTNETLINK answers: File exists
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service: control process exited, code=exited status=1
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Failed to start LSB: Bring up/down networking.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: Unit network.service entered failed state.
Sep 04 17:46:41 testbig04.isky.com systemd[1]: network.service failed.
解决办法：
接关闭 NetworkManger ：
service NetworkManager stop
禁止开机启动：
chkconfig NetworkManager off
重启机器：
reboot
