一、修改01-network-manager-all.yaml文件

先备份01-network-manager-all.yaml文件：

cp /etc/netplan/01-network-manager-all.yaml /etc/netplan/01-network-manager-all.yaml.bak

打开01-network-manager-all.yaml文件：

sudo vi /etc/netplan/01-network-manager-all.yaml

修改成以下内容：

#Let NetworkManager manage all devices on this system
network:
  version: 2
#  renderer: NetworkManager
  ethernets:
          eth0:
                  addresses: [168.168.100.111/16]
                  gateway4:  168.168.0.1
                  dhcp4: no
                  dhcp6: no
                  nameservers: 
                        addresses: [127.0.0.53, 114.114.114.114, 114.114.115.115, 8.8.8.8, 8.8.4.4]

注意：

• eth0为网络设备接口名称，addressed为需要配置的ip地址信息，后面的16为子网掩码,代表255.255.0.0，需要用命令ifconfig -a查看自己的网络信息进行配置
• gateway4为ip4网关，不清楚网关可执行命令route -n进行查看
• nameservers下addresses为DNS地址，国内一般选择114.114.114.114或者114.114.115.115

二、修改resolved.conf文件

先备份resolved.conf文件：

cp /etc/systemd/resolved.conf /etc/systemd/resolved.conf.bak

打开resolved.conf文件：

sudo vi /etc/systemd/resolved.conf

修改成以下内容：

#  This file is part of systemd.
#
#  systemd is free software; you can redistribute it and/or modify it
#  under the terms of the GNU Lesser General Public License as published by
#  the Free Software Foundation; either version 2.1 of the License, or
#  (at your option) any later version.
#
# Entries in this file show the compile time defaults.
# You can change settings by editing this file.
# Defaults can be restored by simply deleting this file.
#
# See resolved.conf(5) for details

[Resolve]
DNS=127.0.0.53 114.114.114.114 114.114.115.115 8.8.8.8 8.8.4.4
#FallbackDNS=
#Domains=
#LLMNR=no
#MulticastDNS=no
#DNSSEC=no
#Cache=yes
#DNSStubListener=yes

三、网络IP相关知识

如果想了解网络IP相关知识，推荐参考文章：

https://blog.csdn.net/weixin_42724467/article/details/90293151