IPv6 DNS解析-Ubuntu20.04

Question

我已经安装了Ubuntu20.04，我不能让IPv6工作。有人能帮帮我吗？

$解析-6查询google.com

google.com: 2a00:1450:4003:801::200e           -- link: wlo1

-- Information acquired via protocol DNS in 16.2ms.
-- Data is authenticated: no

好的

$解析-6查询askubuntu.com

askubuntu.com: resolve call failed: 'askubuntu.com' does not have any RR of the requested type

失败

$解析-4查询askubuntu.com

askubuntu.com: 151.101.1.69                    -- link: wlo1
               151.101.65.69                   -- link: wlo1
               151.101.193.69                  -- link: wlo1
               151.101.129.69                  -- link: wlo1

-- Information acquired via protocol DNS in 18.3ms.
-- Data is authenticated: no

好的，如果使用IPv4。

$ cat /var/run/NetworkManager/resolv.conf
# Generated by NetworkManager
nameserver 127.0.0.53
$ cat /var/run/NetworkManager/no-stub-resolv.conf
# Generated by NetworkManager
nameserver 8.8.8.8

$ cat /var/run/NetworkManager/resolv.conf
# Generated by NetworkManager
nameserver 127.0.0.53
$ cat /var/run/NetworkManager/no-stub-resolv.conf
# Generated by NetworkManager
nameserver 2001:4860:4860::8888

$ systemd-resolve --status
Global
       LLMNR setting: no                  
MulticastDNS setting: no                  
  DNSOverTLS setting: no                  
      DNSSEC setting: no                  
    DNSSEC supported: no                  
          DNSSEC NTA: 10.in-addr.arpa     
                      16.172.in-addr.arpa 
                      168.192.in-addr.arpa
                      17.172.in-addr.arpa 
                      18.172.in-addr.arpa 
                      19.172.in-addr.arpa 
                      20.172.in-addr.arpa 
                      21.172.in-addr.arpa 
                      22.172.in-addr.arpa 
                      23.172.in-addr.arpa 
                      24.172.in-addr.arpa 
                      25.172.in-addr.arpa 
                      26.172.in-addr.arpa 
                      27.172.in-addr.arpa 
                      28.172.in-addr.arpa 
                      29.172.in-addr.arpa 
                      30.172.in-addr.arpa 
                      31.172.in-addr.arpa 
                      corp                
                      d.f.ip6.arpa        
                      home                
                      internal            
                      intranet            
                      lan                 
                      local               
                      private             
                      test                

Link 2 (wlo1)
      Current Scopes: DNS                 
DefaultRoute setting: yes                 
       LLMNR setting: yes                 
MulticastDNS setting: no                  
  DNSOverTLS setting: no                  
      DNSSEC setting: no                  
    DNSSEC supported: no                  
         DNS Servers: 2001:4860:4860::8888
          DNS Domain: ~.

$ cat /etc/nsswitch.conf

# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.

passwd:         files systemd
group:          files systemd
shadow:         files
gshadow:        files

hosts:          files resolve [!UNAVAIL=return] dns
networks:       files

protocols:      db files
services:       db files
ethers:         db files
rpc:            db files

netgroup:       nis

编辑：有一个问题。我无法访问askubuntu.com网站。问题在于我的NetworkManager配置。我已经将IPv4方法设置为“禁用”，而我真正想要的只是“需要IPv6寻址才能完成此连接”。不过，行为太酷了！

Answer 1

从这里看，askubuntu.com似乎没有任何AAAA (IPv6) DNS记录。毕竟，并不是所有事情都是这样的。这并不是说你以前没有去过它，而是因为它对任何人都不存在。

Answer 2

使用dig并指定AAAA作为记录类型，以确定问题是与网络相关的还是与系统相关的。

root@ubuntu:~# dig google.com AAAA

; <<>> DiG 9.10.3-P4-Ubuntu <<>> google.com AAAA
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64485
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1452
;; QUESTION SECTION:
;google.com.                    IN      AAAA

;; ANSWER SECTION:
google.com.             240     IN      AAAA    2607:f8b0:4006:804::200e

;; Query time: 2 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Wed May 06 21:21:59 UTC 2020
;; MSG SIZE  rcvd: 77

如果这样做有效，至少会缩小问题的范围。