补充 Linux 网络桥接 部分.

Signed-off-by: chen.yang <chen.yang@yuzhen-iot.com>

Software/Development/System/Linux/User/Linux_常用目录_文件集合.md

@@ -5,6 +5,7 @@
 | /etc/systemd/system                            | Systemd 服务配置目录 |
 | /lib/firmware                                  | 设备固件目录，该目录下保存着设备运行时所需的固件程序 |
 | /lib/systemd/system                            | Systemd unit files 一般指向 /usr/lib/systemd/system |
+| /proc/sys/net/ipv4/conf                        | 可在该目录下查看创建的和已经存在的网卡设备文件 |
 | /sys/class/drm/card\<n\>-\<Type\>-\<n\>/status | 显示设备状态 |
 | /sys/class/drm/card\<n\>-\<Type\>-\<n\>/modes  | 显示设备所支持的显示模式 |
 | /sys/class/drm/card\<n\>-\<Type\>-\<n\>/edid   | 如果包含 EDID，此节点为映射的 EDID 文件|

Software/System/Linux/Modules/Network/Linux_网络配置.md

@@ -162,3 +162,21 @@ sudo systemctl restart networking.service
 ```
 
 一般而言，/etc/resolv.conf 文件是个软链接，其配置比较复杂，推荐使用 resolvconf 工具进行配置。
+
+## 桥接
+
+```bash
+# Create a new bridge and change its state to up
+ip link add name <bridge name> type bridge
+ip link set <bridge name> up
+# To add an interface (e.g. eth0) into the bridge, its state must be up
+ip link set <eth interface> up
+ip link set <eth interface> master <bridge name>
+# Show the existing bridges and associated interfaces
+bridge -d link
+# OR
+brctl show
+# This is how to remove an interface from a bridge
+ip link set <eth interface> nomaster
+ip link delete <bridge name> type bridge
+```