升级到 18.04 后，我无法连接到 Ubuntu 中的特定网络。它显示已连接，但我无法访问互联网。当我尝试使用移动热点访问时，它工作正常。
ifconfig的结果：
eth0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether 10:bf:48:09:7b:a3 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 369 bytes 34749 (34.7 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 369 bytes 34749 (34.7 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
tun0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500
inet 10.8.0.1 netmask 255.255.255.0 destination 10.8.0.1
inet6 fe80::e8e9:1762:a6fb:d77a prefixlen 64 scopeid 0x20<link>
unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 100 (UNSPEC)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 352 bytes 22027 (22.0 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
tun1: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST> mtu 1500
inet 10.8.0.2 netmask 255.255.255.0 destination 10.8.0.2
inet6 fe80::6ffb:a140:5d12:5359 prefixlen 64 scopeid 0x20<link>
unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 txqueuelen 100 (UNSPEC)
RX packets 9 bytes 1040 (1.0 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 10 bytes 1088 (1.0 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
wlan0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.1.3 netmask 255.255.255.0 broadcast 192.168.1.255
inet6 fe80::5e2e:88d6:f08:a049 prefixlen 64 scopeid 0x20<link>
ether dc:85:de:22:1d:66 txqueuelen 1000 (Ethernet)
RX packets 97 bytes 18444 (18.4 KB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 134 bytes 19607 (19.6 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
路线结果：
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 srikar-K55VM 128.0.0.0 UG 0 0 0 tun0
default csp1.zte.com.cn 0.0.0.0 UG 600 0 0 wlan0
10.8.0.0 0.0.0.0 255.255.255.0 U 0 0 0 tun0
10.8.0.0 0.0.0.0 255.255.255.0 U 0 0 0 tun1
128.0.0.0 srikar-K55VM 128.0.0.0 UG 0 0 0 tun0
link-local 0.0.0.0 255.255.0.0 U 1000 0 0 tun0
192.168.1.0 0.0.0.0 255.255.255.0 U 600 0 0 wlan0
srikar-k55vm 0.0.0.0 255.255.255.255 UH 0 0 0 wlan0
当它第一次发生时，我尝试过
sudo apt-get purge bcmwl-kernel-source
sudo modprobe -r b43
sudo modprobe -r ssb
当时它工作正常。但是当我切换到热点一段时间并再次回到之前的网络时，它就停止工作了。此后，即使上述命令也无济于事。
“lspci -knn | grep Net -A3”的结果
03:00.0 Network controller [0280]: Qualcomm Atheros AR9485 Wireless Network Adapter [168c:0032] (rev 01)
Subsystem: AzureWave AR9485 Wireless Network Adapter [1a3b:2c97]
Kernel driver in use: ath9k
Kernel modules: ath9k
04:00.0 Unassigned class [ff00]: Realtek Semiconductor Co., Ltd. RTL8411 PCI
Express Card Reader [10ec:5289] (rev 01)
问候， Srikar