新装的Ubuntu无法连接有线（无有线标志）

解决方法

1、lspci命令（查看网卡型号）

labh@lab:~$ lspci
00:00.0 Host bridge: Intel Corporation Device 4660 (rev 02)
00:01.0 PCI bridge: Intel Corporation Device 460d (rev 02)
00:06.0 PCI bridge: Intel Corporation Device 464d (rev 02)
00:0a.0 Signal processing controller: Intel Corporation Device 467d (rev 01)
00:0e.0 RAID bus controller: Intel Corporation Device 467f
00:14.0 USB controller: Intel Corporation Device 7ae0 (rev 11)
00:14.2 RAM memory: Intel Corporation Device 7aa7 (rev 11)
00:14.3 Network controller: Intel Corporation Device 7af0 (rev 11)
00:15.0 Serial bus controller [0c80]: Intel Corporation Device 7acc (rev 11)
00:15.1 Serial bus controller [0c80]: Intel Corporation Device 7acd (rev 11)
00:15.2 Serial bus controller [0c80]: Intel Corporation Device 7ace (rev 11)
00:16.0 Communication controller: Intel Corporation Device 7ae8 (rev 11)
00:17.0 SATA controller: Intel Corporation Device 7ae2 (rev 11)
00:1a.0 PCI bridge: Intel Corporation Device 7ac8 (rev 11)
00:1b.0 PCI bridge: Intel Corporation Device 7ac0 (rev 11)
00:1c.0 PCI bridge: Intel Corporation Device 7ab8 (rev 11)
00:1c.2 PCI bridge: Intel Corporation Device 7aba (rev 11)
00:1d.0 PCI bridge: Intel Corporation Device 7ab0 (rev 11)
00:1f.0 ISA bridge: Intel Corporation Device 7a84 (rev 11)
00:1f.3 Audio device: Intel Corporation Device 7ad0 (rev 11)
00:1f.4 SMBus: Intel Corporation Device 7aa3 (rev 11)
00:1f.5 Serial bus controller [0c80]: Intel Corporation Device 7aa4 (rev 11)
01:00.0 VGA compatible controller: NVIDIA Corporation Device 2204 (rev a1)
01:00.1 Audio device: NVIDIA Corporation Device 1aef (rev a1)
02:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd Device a80a
06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. Device 8125 (rev 05)

看到最后一行

06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. Device 8125 (rev 05)

因此我们的网卡驱动版本为8125

2、官网下载

官网网址：Realtek PCIe FE / GBE / 2.5G / Gaming Ethernet Family Controller Software - REALTEK

 对应为2.5G Ethernet LINUX driver r8125 for kernel up to 5.19的这个文件

进行下载

3、安装

下载完成后是tar.bz2格式

解压命令：tar   -jxvf    xx.tar.bz2

解压后进入文件夹，找到autorun.sh 执行以下命令安装

sudo sh ./autorun.sh

安装完成可以发现插上网线已经可以上网了