CentOS 7 Failed to start LSB: Bring up/down networking

今天用xshell連接虛擬機的時候，突然連接不上，就到虛擬機上去查一下原因，原來是network 啓動不了，文檔上說要disable NetworkManager, 用 network服務纔行。

我用 systemctl network start命令啓動時報錯：

[root@localhost network-scripts]# systemctl network start
Starting network (via systemctl): Job for network.service failed. See ‘systemctl status network.service’ and ‘journalctl -xn’ for details.[FAILED]
[root@localhost network-scripts]# systemctl status network.service

• LSB: Bring up/down networking Loaded: loaded (/etc/rc.d/init.d/network) Active: failed (Result: exit-code) since Sat 2015-03-07 02:53:12 EST; 6s ago Process: 8596 ExecStart=/etc/rc.d/init.d/network start (code=exited, status=1/FAILURE)Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain network[8596]: RTNETLINK answers: File …Mar 07 02:53:12 localhost.localdomain systemd-sysctl[8913]: Overwriting earli…Mar 07 02:53:12 localhost.localdomain systemd[1]: network.service: control pr…Mar 07 02:53:12 localhost.localdomain systemd[1]: Failed to start LSB: Bring …Mar 07 02:53:12 localhost.localdomain systemd[1]: Unit network.service entere…Hint: Some lines were ellipsized, use -l to show in full.

然後網上搜是因爲沒加HWADDR…這個我確實給刪了…

先看log裏說哪個網卡沒有UP起來：

[root@localhost network-scripts]# cat /var/log/messages | grep network
Mar 7 03:05:18 localhost kernel: drop_monitor: Initializing network drop monitor serviceMar 7 03:05:19 localhost systemd-udevd[413]: renamed network interface eth1 to enp1s0f1Mar 7 03:05:19 localhost systemd-udevd[416]: renamed network interface eth5 to enp8s0f3Mar 7 03:05:19 localhost systemd-udevd[421]: renamed network interface eth3 to enp8s0f1Mar 7 03:05:19 localhost systemd-udevd[429]: renamed network interface eth4 to enp8s0f2Mar 7 03:05:19 localhost systemd-udevd[411]: renamed network interface eth0 to enp1s0f0Mar 7 03:05:19 localhost systemd-udevd[419]: renamed network interface eth2 to enp8s0f0Mar 7 03:05:25 localhost systemd-udevd[412]: renamed network interface eth1 to enp3s0f1Mar 7 03:05:25 localhost systemd-udevd[414]: renamed network interface eth3 to enp131s0f1Mar 7 03:05:25 localhost systemd-udevd[411]: renamed network interface eth0 to enp3s0f0Mar 7 03:05:25 localhost systemd-udevd[413]: renamed network interface eth2 to enp131s0f0Mar 7 03:05:25 localhost systemd-udevd[415]: renamed network interface eth4 to enp134s0f0Mar 7 03:05:25 localhost systemd-udevd[416]: renamed network interface eth5 to enp134s0f1Mar 7 03:05:30 localhost systemd: Starting Import network configuration from initramfs…Mar 7 03:05:30 localhost systemd: Started Import network configuration from initramfs.Mar 7 03:05:40 localhost systemd: Starting Rollback uncommitted netcf network config change transactions…Mar 7 03:05:40 localhost systemd: Started Rollback uncommitted netcf network config change transactions.Mar 7 03:05:43 localhost systemd: Starting LSB: Bring up/down networking…Mar 7 03:05:45 localhost network: Bringing up loopback interface: [ OK ]Mar 7 03:05:45 localhost network: Bringing up interface br0: ERROR : [/etc/sysconfig/network-scripts/ifup-eth] Device br0 does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost /etc/sysconfig/network-scripts/ifup-eth: Device br0 does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost network: [FAILED]Mar 7 03:05:45 localhost network: Bringing up interface enp1s0f0: [ OK ]Mar 7 03:05:45 localhost network: Bringing up interface enp8s0f0: ERROR : [/etc/sysconfig/network-scripts/ifup-eth] Device does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost /etc/sysconfig/network-scripts/ifup-eth: Device does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost network: [FAILED]Mar 7 03:05:45 localhost network: Bringing up interface enp8s0f1: ERROR : [/etc/sysconfig/network-scripts/ifup-eth] Device does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost /etc/sysconfig/network-scripts/ifup-eth: Device does not seem to be present, delaying initialization.Mar 7 03:05:45 localhost network: [FAILED]Mar 7 03:05:45 localhost systemd: network.service: control process exited, code=exited status=1Mar 7 03:05:45 localhost systemd: Failed to start LSB: Bring up/down networking.Mar 7 03:05:45 localhost systemd: Unit network.service entered failed state.Mar 7 03:05:48 localhost xinetd[1863]: xinetd Version 2.3.15 started with libwrap loadavg labeled-networking options compiled in.

ip addr查看這倆網卡的MAC：

[root@localhost network-scripts]# ip addr
1: lo: mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever2: enp1s0f0: mtu 1500 qdisc mq master br0 state UP qlen 1000 link/ether 00:25:90:64:a9:30 brd ff:ff:ff:ff:ff:ff inet6 fe80::225:90ff:fe64:a930/64 scope link valid_lft forever preferred_lft forever3: enp1s0f1: mtu 1500 qdisc noop state DOWN qlen 1000 link/ether 00:25:90:64:a9:31 brd ff:ff:ff:ff:ff:ff4: enp8s0f0: mtu 1500 qdisc noop state DOWN qlen 1000 link/ether 00:0c:bd:05:4e:cc brd ff:ff:ff:ff:ff:ff5: enp8s0f1: mtu 1500 qdisc noop state DOWN qlen 1000 link/ether 00:0c:bd:05:4e:cd brd ff:ff:ff:ff:ff:ff6: enp8s0f2: mtu 1500 qdisc noop state DOWN qlen 1000 link/ether 00:0c:bd:05:4e:ce brd ff:ff:ff:ff:ff:ff7: enp8s0f3: mtu 1500 qdisc noop state DOWN qlen 1000 link/ether 00:0c:bd:05:4e:cf brd ff:ff:ff:ff:ff:ff

然後把這倆網卡的mac寫到配置文件裏：

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

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

添加：
HWADDR=00:0c:bd:05:4e:cc​

然後重新啓動network，就OK啦！

還有一種可能

其實問題不一定是MAC的問題，也有其他的可能性。下面是另一種情況：

虛擬機裏邊的CentOS7重啓之後無法聯網了，重啓network發現報錯。

百度了一圈，都是叫修改mac地址的說法，但是改了之後並沒有什麼用，最後谷歌解決了。

事實證明百度就是個水貨！

解決方式：禁用NetworkManager
下列的命令依次執行：

1. systemctl stop NetworkManager

2. systemctl disable NetworkManager

3. systemctl start network

4. systemctl status network 查看若是顯示的是active 那麼就是好了

5. 也可以ping 8.8.8.8 試試看 是否成功

然後重啓網絡服務，能正常聯網了！