Ubuntu 20.04“名称解析中的临时故障”-最近重新安装

Question

我从contabo那里租了一个vps大约半年，直到现在它还能正常工作，因为它开始产生“名称解析中的临时故障”错误。我读到这是DNS错误，我尝试了nameserver 8.8.8.8和nameserver 1.1.1.1，但是问题仍然存在。

同样在昨天，我完全重新安装了vps，但是它没有工作。

/etc/resolv.conf:

# This file is managed by man:systemd-resolved(8). Do not edit.
#
# This is a dynamic resolv.conf file for connecting local clients to the
# internal DNS stub resolver of systemd-resolved. This file lists all
# configured search domains.
#
# Run "resolvectl status" to see details about the uplink DNS servers
# currently in use.
#
# Third party programs must not access this file directly, but only through the
# symlink at /etc/resolv.conf. To manage man:resolv.conf(5) in a different way,
# replace this symlink by a static file or a different symlink.
#
# See man:systemd-resolved.service(8) for details about the supported modes of
# operation for /etc/resolv.conf.

nameserver 127.0.0.53
options edns0
search invalid

resolvectl状态：

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 (eth0)
      Current Scopes: DNS          
DefaultRoute setting: yes          
       LLMNR setting: yes          
MulticastDNS setting: no           
  DNSOverTLS setting: no           
      DNSSEC setting: no           
    DNSSEC supported: no           
  Current DNS Server: 213.136.95.11
         DNS Servers: 213.136.95.10
                      213.136.95.11
          DNS Domain: invalid 

sudo systemctl status systemd-resolved.service:

● systemd-resolved.service - Network Name Resolution
     Loaded: loaded (/lib/systemd/system/systemd-resolved.service; enabled; vendor preset: enabled)
     Active: active (running) since Thu 2020-05-21 21:45:08 CEST; 1 day 14h ago
       Docs: man:systemd-resolved.service(8)
             https://www.freedesktop.org/wiki/Software/systemd/resolved
             https://www.freedesktop.org/wiki/Software/systemd/writing-network-configuration-managers
             https://www.freedesktop.org/wiki/Software/systemd/writing-resolver-clients
   Main PID: 460 (systemd-resolve)
     Status: "Processing requests..."
      Tasks: 1 (limit: 9487)
     Memory: 7.5M
     CGroup: /system.slice/systemd-resolved.service
             └─460 /lib/systemd/systemd-resolved

May 23 11:59:44 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:00:18 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:00:20 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:00:31 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:00:48 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:01:05 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:01:15 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:01:29 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:01:55 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.
May 23 12:02:21 vmi329703.contaboserver.net systemd-resolved[460]: Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP.

我有个不和谐的机器人，通常问题就出现在那里。

Answer 1

尝试禁用当前生命周期的ipv6

sudo sysctl -w net.ipv6.conf.all.disable_ipv6=1
sudo sysctl -w net.ipv6.conf.default.disable_ipv6=1
sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=1

如果一切正常，那么永久禁用ipv6 (作为临时解决方案)

~$ cat /etc/sysctl.d/10-ipv6-disable.conf 
net.ipv6.conf.all.disable_ipv6=1
net.ipv6.conf.default.disable_ipv6=1
net.ipv6.conf.lo.disable_ipv6=1