查看ubuntu版本
cat /etc/issue
Ubuntu 18.04.6 LTS \n \l
resolved.conf配置示例
vim /etc/systemd/resolved.conf
配置dns信息
# 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=223.6.6.6 223.5.5.5 8.8.8.8 114.114.114.114
FallbackDNS=8.8.8.8
#Domains=
LLMNR=yes
MulticastDNS=yes
#DNSSEC=allow-downgrade
#DNSOverTLS=no
Cache=yes
#DNSStubListener=yes
#ReadEtcHosts=yes
重启systemd-resolved服务
systemctl restart systemd-resolved
查看dns信息
systemd-resolve --status | grep 'DNS Servers' -A2