最後更新: 2020-07-21

介紹

Centos 8 會有它 (Default: 啟用)

provides network name resolution to local applications via a D-Bus interface

It implements a caching and validating DNS/DNSSEC stub resolver

(LLMNR / MulticastDNS resolver and responder)

Port: 9355/TCP

CLI

# Restart service

systemctl restart systemd-resolved

# Status

resolvectl

Global
           Protocols: -LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
    resolv.conf mode: stub
  Current DNS Server: 1.1.1.1
         DNS Servers: 1.1.1.1 1.0.0.1
Fallback DNS Servers: 8.8.8.8 8.8.4.4

Link 2 (ens160)
    Current Scopes: DNS
         Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: 1.1.1.1
       DNS Servers: 1.1.1.1 1.0.0.1

resolvectl status ens160

Link 2 (ens160)
    Current Scopes: DNS
         Protocols: +DefaultRoute +LLMNR -mDNS -DNSOverTLS DNSSEC=no/unsupported
Current DNS Server: 1.1.1.1
       DNS Servers: 1.1.1.1 1.0.0.1

# Set nameserver

resolvectl dns ens160 1.1.1.1 1.0.0.1

# Test

resolvectl query hk.yahoo.com

# Cache

resolvectl flush-caches

# Generated by systemd-resolved

cat /run/systemd/resolve/resolv.conf

Ubuntu

Config

• /etc/systemd/resolved.conf
• /etc/systemd/resolved.conf.d/

resolved.conf

[Resolve]
# A space-separated list of IPv4 and IPv6 addresses
DNS=1.1.1.1 1.0.0.1
FallbackDNS=8.8.8.8 8.8.4.4

Help

man resolved.conf

Centos

Global settings:

FILES: /etc/systemd/resolved.conf (Or /etc/systemd/resolved.conf.d/resolved.conf)

[Resolve]
#DNS=
#FallbackDNS=
#Domains=
#LLMNR=yes
#MulticastDNS=yes
#DNSSEC=allow-downgrade
#DNSOverTLS=no
#Cache=yes
#DNSStubListener=udp

Per-link dynamic settings

FILES: /etc/systemd/network/*.network