☰

DNS_PROBE_FINISHED_NXDOMAIN 且网络不可访问

tag-icon • tag-icon networking network-manager 20.04 router
DNS_PROBE_FINISHED_NXDOMAIN 且网络不可访问

我的公寓里有一台 UBEE EVW321B 路由器，它用作信号分配器/交换机，通过墙上的以太网端口接收来自楼下 ISP 路由器的信号。

该接入点为六个人提供互联网，他们现在家里都有相同的设置。这个设置已经工作了两年，提供稳定的互联网。突然间，我们的有线和无线网络都出现了连接问题和中断。没有定期维护，我认为这与冠状病毒和人们在家工作导致的网络负载增加无关，这是我邻居们一段时间以来的理论。

浏览器显示错误：DNS_PROBE_FINISHED_NXDOMAIN

采取的步骤：

  1. 多次重启接入点
  2. 多次重启我自己的网络交换机（又名 UBEE 路由器）
  3. 将 UBEE 路由器重置为出厂设置
  4. 通过硬件重新启动 Ubuntu 20.04 上的网络管理器，但也通过 GUI @ 192.168.178.1（所以我知道我的路由器 IP 有时可以工作）
  5. 关注此博客

输出如下：

➜  ~ ip addr                 
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: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether f0:79:59:62:27:6f brd ff:ff:ff:ff:ff:ff
    inet6 2001:1c00:e13:bf00:a868:7c0c:611e:1c7b/64 scope global temporary dynamic 
       valid_lft 41459sec preferred_lft 12659sec
    inet6 2001:1c00:e13:bf00:8179:e459:9d1e:6285/64 scope global dynamic mngtmpaddr noprefixroute 
       valid_lft 41459sec preferred_lft 12659sec
    inet6 fe80::fe60:fbd6:cbc9:4f46/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

➜  ~ route -n                
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

➜  ~ ping 192.168.178.1
ping: connect: Network is unreachable

➜  ~ ping 8.8.8.8
ping: connect: Network is unreachable

➜  ~ ping google.com
PING google.com(ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e)) 56 data bytes
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=1 ttl=53 time=12.2 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=2 ttl=53 time=12.4 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=3 ttl=53 time=17.7 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=4 ttl=53 time=9.35 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=5 ttl=53 time=26.0 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=6 ttl=53 time=17.4 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=7 ttl=53 time=11.1 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=8 ttl=53 time=10.2 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=9 ttl=53 time=9.78 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=10 ttl=53 time=11.0 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=11 ttl=53 time=9.82 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=12 ttl=53 time=10.6 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=13 ttl=53 time=9.09 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=14 ttl=53 time=9.89 ms
64 bytes from ams15s40-in-x0e.1e100.net (2a00:1450:400e:80d::200e): icmp_seq=15 ttl=53 time=10.5 ms
^C
--- google.com ping statistics ---
15 packets transmitted, 15 received, 0% packet loss, time 14021ms
rtt min/avg/max/mdev = 9.089/12.460/25.988/4.425 ms

然后运行

➜  ~ sudo service network-manager restart

➜  ~ route -n                            
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

进而！！！

➜  ~ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.178.1   0.0.0.0         UG    20100  0        0 enp3s0
192.168.178.0   0.0.0.0         255.255.255.0   U     100    0        0 enp3s0

但五分钟后又回到同样的故事 :(

➜  ~ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

➜  ~ netstat -nr                                
Kernel IP routing table 
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface

相关内容