我的笔记本电脑与本地 wifi 的连接出现了一些奇怪的现象。连接似乎毫无原因地受到限制，而且完全是随机的。这种情况平均每小时发生一次。以下是 nmcli 显示的内容：
stefano@stefano-Latitude-E7240:~$ nmcli g
STATE CONNECTIVITY WIFI-HW WIFI WWAN-HW WWAN
connected (site only) limited enabled enabled enabled enabled
要解决这个问题，只需重新启动网络管理器小程序即可。当然，这只是一个临时解决方案。我试图通过在互联网上 ping 不同的 IP 来了解问题的根源。我的虚拟故障排除结果：
- 我可以 ping 网关
- 我可以 ping 任何 IP 地址
- 我无法 ping 主机名
所以我猜这个问题与 DNS 名称解析有关。我该如何解决这个问题？下面是 resolv.conf 的内容和 uname 的输出。
stefano@stefano-Latitude-E7240:~$ cat /etc/resolv.conf
# Generated by NetworkManager
nameserver 127.0.0.53
stefano@stefano-Latitude-E7240:~$ uname -a
Linux stefano-Latitude-E7240 4.18.0-17-generic #18-Ubuntu SMP Wed Mar 13 14:34:40 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
先感谢您。
编辑：其他所需信息：
stefano@stefano-Latitude-E7240:~$ nmcli d
DEVICE TYPE STATE CONNECTION
wlp2s0 wifi connected FASTWEB-XE5.0GHZ
eno1 ethernet unavailable --
lo loopback unmanaged --
stefano@stefano-Latitude-E7240:~$ ip addr show
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: eno1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN group default qlen 1000
link/ether ec:f4:bb:67:3b:75 brd ff:ff:ff:ff:ff:ff
3: wlp2s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether f8:16:54:ba:71:74 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.206/24 brd 192.168.1.255 scope global dynamic noprefixroute wlp2s0
valid_lft 84662sec preferred_lft 84662sec
inet6 2001:b07:5d29:9741:49b8:1d36:d9df:f637/64 scope global temporary dynamic
valid_lft 603064sec preferred_lft 84287sec
inet6 2001:b07:5d29:9741:e11e:4a67:e846:1e/64 scope global mngtmpaddr noprefixroute
valid_lft forever preferred_lft forever
inet6 fe80::94bf:18ac:a222:89c/64 scope link noprefixroute
valid_lft forever preferred_lft forever
stefano@stefano-Latitude-E7240:~$ sudo lshw -short -class network
[sudo] password for stefano:
H/W path Device Class Description
======================================================
/0/100/19 eno1 network Ethernet Connection I218-LM
/0/100/1c.3/0 wlp2s0 network Wireless 7260
stefano@stefano-Latitude-E7240:~$ rfkill
ID TYPE DEVICE SOFT HARD
1 wlan dell-wifi unblocked unblocked
2 bluetooth dell-bluetooth unblocked unblocked
3 wlan phy0 unblocked unblocked
15 nfc nfc0 unblocked unblocked
17 bluetooth hci0 unblocked unblocked
stefano@stefano-Latitude-E7240:~$ cat /etc/hosts
127.0.0.1 localhost
127.0.1.1 stefano-Latitude-E7240
# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
编辑2：
stefano@stefano-Latitude-E7240:~$ hostname
stefano-Latitude-E7240
stefano@stefano-Latitude-E7240:~$ nmcli device show wlp2s0 | grep IP4.DNS
IP4.DNS[1]: 192.168.1.254
IP4.DNS[2]: 8.8.8.8