我检查过：Wifi 已连接但无互联网 和已连接 wifi，但上不了网 [16.04]
https://askubuntu.com/questions/1028651/wifi-connected-but-cannot-access-internet-ubuntu--- 不起作用
除其他来源外...
我已连接到同一网络，并在另一台计算机上访问了互联网。有问题的计算机使用的是 Ubuntu 18.04.3 LTS 并连接到我的路由器。我有一个 IP 地址（来自 wlp1s0）。我无法 ping 8.8.8.8。我不知道我的路由器的 IP，我无法解析名称服务器或通过浏览器连接到互联网。
user@user-S410G2:~$ cat /etc/network/interfaces
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
#post-up ip route add 224.0.0.0/4 dev lo metric 800
user@user-S410G2:~$ sudo service network-manager restart
user@user-S410G2:~$ iwconfig
lo no wireless extensions.
enp0s31f6 no wireless extensions.
wwp0s20f0u5i12 no wireless extensions.
wlp1s0 IEEE 802.11 ESSID:"FRFadmin"
Mode:Managed Frequency:2.437 GHz Access Point: 00:1E:2A:0A:E7:0A
Bit Rate=18 Mb/s Tx-Power=22 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Power Management:on
Link Quality=28/70 Signal level=-82 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:1 Invalid misc:22 Missed beacon:0
user@user-S410G2:~$ ip address
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
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 forever
2: enp0s31f6: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether 00:22:20:1f:6a:85 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.100/24 brd 192.168.1.255 scope global enp0s31f6
valid_lft forever preferred_lft forever
4: wlp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether d4:d2:52:d1:08:62 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.130/24 brd 192.168.1.255 scope global dynamic noprefixroute wlp1s0
valid_lft 86334sec preferred_lft 86334sec
inet6 fe80::2d1f:3795:f831:3593/64 scope link noprefixroute
valid_lft forever preferred_lft forever
7: wwp0s20f0u5i12: <BROADCAST,MULTICAST,NOARP> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 9a:96:15:9a:e6:e1 brd ff:ff:ff:ff:ff:ff
user@user-S410G2:~$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
From 192.168.1.100 icmp_seq=1 Destination Host Unreachable
From 192.168.1.100 icmp_seq=2 Destination Host Unreachable
From 192.168.1.100 icmp_seq=3 Destination Host Unreachable
From 192.168.1.100 icmp_seq=4 Destination Host Unreachable
^C
--- 8.8.8.8 ping statistics ---
5 packets transmitted, 0 received, +4 errors, 100% packet loss, time 4041ms
pipe 3
user@user-S410G2:~$ sudo lshw -class network
*-network
description: Wireless interface
product: Wireless 8265 / 8275
vendor: Intel Corporation
physical id: 0
bus info: pci@0000:01:00.0
logical name: wlp1s0
version: 78
serial: d4:d2:52:d1:08:62
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless
configuration: broadcast=yes driver=iwlwifi driverversion=5.0.0-32-generic firmware=36.9f0a2d68.0 ip=192.168.1.130 latency=0 link=yes multicast=yes wireless=IEEE 802.11
resources: irq:130 memory:a9100000-a9101fff
*-network
description: Ethernet interface
product: Ethernet Connection I219-LM
vendor: Intel Corporation
physical id: 1f.6
bus info: pci@0000:00:1f.6
logical name: enp0s31f6
version: 21
serial: 00:22:20:1f:6a:85
capacity: 1Gbit/s
width: 32 bits
clock: 33MHz
capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=3.2.6-k firmware=0.13-4 ip=192.168.1.100 latency=0 link=no multicast=yes port=twisted pair
resources: irq:134 memory:a9200000-a921ffff
*-network DISABLED
description: Ethernet interface
physical id: 2
logical name: wwp0s20f0u5i12
serial: 9a:96:15:9a:e6:e1
capabilities: ethernet physical
configuration: broadcast=yes driver=cdc_mbim driverversion=22-Aug-2005 firmware=CDC MBIM link=no multicast=yes
上面附有各种调试/故障排除的输出，我认为这些输出似乎与此相关。这似乎是 Ubuntu 的一个普遍问题。非常感谢您的帮助！
答案1
是 wifi 还是以太网导致了这个问题？两者似乎都已连接。/etc/network/interfaces从 Ubuntu 17.10 开始，该文件已被 netplan 替换。我建议您将更改还原到该文件并在网络管理器中设置任何详细信息。如果您要设置静态 IP 地址，请确保还包括 DNS 名称服务器。
进行任何更改后，断开以太网并重新启动网络管理器：
sudo service network-manager restart
wifi 能连上吗？
iwconfig
您能 ping 通路由器吗？
ping -c3 192.168.1.1
您能 ping 通互联网名称服务器吗？
ping -c3 8.8.8.8
你能解析名称吗？
ping -c3 www.ubuntu.com