https://www.cnblogs.com/bonjov1/p/4323836.html

CentOS7 Failed to start LSB: Bring up/down networking.解决方法
今天用CentOS7 RDO方式安装Openstack，文档上说要disable NetworkManager, 用 network服务才行。

但是我用 service network start命令启动时报错：

[root@localhost network-scripts]# service network start

Starting network (via systemctl):  Job -- :: EST; 6s ago  Process:  ExecStart=/etc/rc.d/init.d/network start (code=exited, status=/FAILURE)Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain network[]: RTNETLINK answers: File ...Mar  :: localhost.localdomain systemd-sysctl[]: Overwriting earli...Mar  :: localhost.localdomain systemd[]: network.service: control pr...Mar  :: localhost.localdomain systemd[]: Failed to start LSB: Bring ...Mar  :: localhost.localdomain systemd[]: Unit network.service entere...Hint: Some lines were ellipsized, use -l to show in full.

然后网上搜是因为没加HWADDR....这个我确实给删了....

先看log里说哪个网卡没有UP起来：

[root@localhost network-scripts]# cat /var/log/messages | grep network

Mar   :: localhost kernel: drop_monitor: Initializing network drop monitor serviceMar   :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd-udevd[]: renamed network  :: localhost systemd: Starting Import network configuration  :: localhost systemd: Started Import network configuration  :: localhost systemd: Starting Rollback uncommitted netcf network config change transactions...Mar   :: localhost systemd: Started Rollback uncommitted netcf network config change transactions.Mar   :: localhost systemd: Starting LSB: Bring up/down networking...Mar   :: localhost network: Bringing up loopback  :: localhost network: Bringing up  :: localhost /etc/sysconfig/network-scripts/ifup-eth: Device br0 does not seem to be present, delaying initialization.Mar   :: localhost network: [FAILED]Mar   :: localhost network: Bringing up  :: localhost network: Bringing up  :: localhost /etc/sysconfig/network-scripts/ifup-eth: Device  does not seem to be present, delaying initialization.Mar   :: localhost network: [FAILED]Mar   :: localhost network: Bringing up  :: localhost /etc/sysconfig/network-scripts/ifup-eth: Device  does not seem to be present, delaying initialization.Mar   :: localhost network: [FAILED]Mar   :: localhost systemd: network.service: control process exited, code=exited status=1Mar   :: localhost systemd: Failed to start LSB: Bring up/down networking.Mar   :: localhost systemd: Unit network.service entered failed state.Mar   :: localhost xinetd[]: xinetd Version  started with libwrap loadavg labeled-networking options compiled in.

ip addr查看这俩网卡的MAC：

[root@localhost network-scripts]# ip addr

: lo: mtu  qdisc noqueue state UNKNOWN     link/loopback ::::: brd :::::    inet  scope host lo       valid_lft forever preferred_lft forever    inet6 ::/ scope host        valid_lft forever preferred_lft forever2: enp1s0f0: mtu  qdisc mq master br0 state UP qlen     link/ether ::::a9: brd ff:ff:ff:ff:ff:ff    inet6 fe80:::90ff:fe64:a930/ scope link        valid_lft forever preferred_lft forever3: enp1s0f1: mtu  qdisc noop state DOWN qlen     link/ether ::::a9: brd ff:ff:ff:ff:ff:ff4: enp8s0f0: mtu  qdisc noop state DOWN qlen     link/ether :0c:bd::4e:cc brd ff:ff:ff:ff:ff:ff5: enp8s0f1: mtu  qdisc noop state DOWN qlen     link/ether :0c:bd::4e:cd brd ff:ff:ff:ff:ff:ff6: enp8s0f2: mtu  qdisc noop state DOWN qlen     link/ether :0c:bd::4e:ce brd ff:ff:ff:ff:ff:ff7: enp8s0f3: mtu  qdisc noop state DOWN qlen     link/ether :0c:bd::4e:cf brd ff:ff:ff:ff:ff:ff

然后把这俩网卡的mac写到配置文件里：

/etc/sysconfig/network-scripts/ifcfg-enp8s0f0

/etc/sysconfig/network-scripts/ifcfg-enp8s0f1

​​

添加：

HWADDR=:0c:bd::4e:cc​

然后重新启动network，就OK啦！

很久没更新了，其实问题不一定是MAC的问题，也有其他的可能性。下面是另一种情况：

虚拟机里边的CentOS7重启之后无法联网了，重启network发现报错。

百度了一圈，都是叫修改mac地址的说法，但是改了之后并没有什么用，最后谷歌解决了。

事实证明百度就是个水货！

解决方式：禁用NetworkManager

. systemctl stop NetworkManager
. systemctl disable NetworkManager

然后重启网络服务，能正常联网了！