ubuntu 20.04无法连接网络，网线灯不亮，network

网线灯不亮，network"/>

ubuntu 20.04无法连接网络，网线灯不亮，network

背景

系统编程只读的了，进入到initramfs模式，执行了下边语句，发现不小心把windows也给执行了，报错很多乱码，强制退出
执行

fsck -y /dev/sdb4
fsck -t ext4 /dev/sdb5  -y ## windows

时强制退出了导致很多文件损坏,虽然能正常开机了
但是terminal打不开，NetworkManager启动不了，网卡也掉了，折腾了好久才解决重新连上网

解决办法

看系统日志报错,网线灯也不亮

bus-manager: fatal failure to acquire D-Bus service "org.freedesktop.NetworkManager: GDBus.Error:org.freedesktop.DBus.Error.AccessDenied: Connection ":1.293" is not allowed to own the service "org.freedesktop.NetworkManager" due to security policies in the configuration fil

挂载网卡

1. 找个可以打开的控制台工具打开，我用vscode打开控制台
   执行语句挂在网卡,网卡灯就亮了，我的网卡名字叫eno1,有些网卡叫eth0什么的多试试就行

ifconfig eno1 up

启动network-manager

1. 启动网卡还是失败，报上边的错误

sudo service network-manager start

创建一个文件叫org.freedesktop.NetworkManager.conf,拷贝到

sudo cp org.freedesktop.NetworkManager.conf /etc/dbus-1/system.d/

内容如下：

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE busconfig PUBLIC"-//freedesktop//DTD D-BUS Bus Configuration 1.0//EN"".0/busconfig.dtd">
<busconfig><!-- Only root can own the service --><policy user="root"><allow own="org.freedesktop.NetworkManager"/></policy><policy context="default"><allow send_destination="org.freedesktop.NetworkManager"/><allow send_destination="org.freedesktop.NetworkManager"send_interface="org.freedesktop.DBus.Properties"/><allow send_destination="org.freedesktop.NetworkManager"send_interface="org.freedesktop.DBus.Introspectable"/><allow send_destination="org.freedesktop.NetworkManager.User"send_interface="org.freedesktop.DBus.Properties"/><allow send_destination="org.freedesktop.NetworkManager.User"send_interface="org.freedesktop.DBus.Introspectable"/></policy></busconfig>

再次启动network-manager,启动成功

sudo service network-manager start

查看窗台

sudo service network-manager status

获取ipv4地址

1. 启动成功但是还是无法获取ipv4地址

需要创建一个/etc/network/interfaces文件，内容如下： 网卡改成你自己的

 auto loiface lo inet loopbackauto eno1iface eno1 inet dhcpauto eno1iface eno1 inet dhcp

执行

sudo dhclient

就有ipv4地址了，可以正常连接