Temporary failure in name resolution

[James2021]

Hi,

I've been working since a year with proxmox everything was smooth until suddenly there is an issue with name resolution.

root@proxmox:~# ping google.com
ping: google.com: Temporary failure in name resolution

Here is my configuration:

root@proxmox:~# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s31f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master vmbr0 state UP group default qlen 1000
    link/ether 30:9c:23:21:bc:9c brd ff:ff:ff:ff:ff:ff
3: vmbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 30:9c:23:21:bc:9c brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.10/24 brd 192.168.0.255 scope global vmbr0
       valid_lft forever preferred_lft forever
    inet6 fe80::329c:23ff:fe21:bc9c/64 scope link
       valid_lft forever preferred_lft forever

root@proxmox:~# cat /etc/network/interfaces
auto lo
iface lo inet loopback

iface enp0s31f6 inet manual

auto vmbr0
iface vmbr0 inet static
        address 192.168.0.10
        netmask 255.255.255.0
        gateway 192.168.0.1
        dns-nameservers 8.8.8.8 1.1.1.1
        bridge_ports enp0s31f6
        bridge_stp off
        bridge_fd 0

#auto enp0s31f6
#iface enp0s31f6 inet static
#       address 192.168.0.10/24
#       gateway 192.168.0.1

#auto enx00e04c365a9e
#iface enx00e04c365a9e inet static
#       address 192.168.0.11/24
#       gateway 192.168.0.1

nano /etc/resolv.conf
nameserver 8.8.8.8


Also I don't know why in the below service (echo "nameserver 127.0.0.53") shouldn't be 8.8.8.8

root@proxmox:/etc# systemctl status systemd-resolved.service
● systemd-resolved.service - Network Name Resolution
   Loaded: loaded (/lib/systemd/system/systemd-resolved.service; disabled; vendor preset: enabled)
  Drop-In: /usr/lib/systemd/system/systemd-resolved.service.d
           └─resolvconf.conf
   Active: active (running) since Fri 2021-12-03 13:10:35 EET; 1min 11s 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
  Process: 3788 ExecStartPost=/bin/sh -c [ ! -e /run/resolvconf/enable-updates ] || echo "nameserver 127.0.0.53" | /sbin
 Main PID: 3781 (systemd-resolve)
   Status: "Processing requests..."
    Tasks: 1 (limit: 4915)
   Memory: 2.8M
   CGroup: /system.slice/systemd-resolved.service
           └─3781 /lib/systemd/systemd-resolved

Dec 03 13:10:34 proxmox systemd[1]: Starting Network Name Resolution...
Dec 03 13:10:35 proxmox systemd-resolved[3781]: Positive Trust Anchors:
Dec 03 13:10:35 proxmox systemd-resolved[3781]: . IN DS 19036 8 2 49aac11d7b6f6446702e54a1607371607a1a41855200fd2ce1cdde
Dec 03 13:10:35 proxmox systemd-resolved[3781]: . IN DS 20326 8 2 e06d44b80b8f1d39a95c0b0d7c65d08458e880409bbc6834571042
Dec 03 13:10:35 proxmox systemd-resolved[3781]: Negative trust anchors: 10.in-addr.arpa 16.172.in-addr.arpa 17.172.in-ad
Dec 03 13:10:35 proxmox systemd-resolved[3781]: Using system hostname 'proxmox'.
Dec 03 13:10:35 proxmox systemd[1]: Started Network Name Resolution.

Your help is really appreciated, I've spent days on this.

 

[t.lamprecht]

Is network itself working, i.e., ping 8.8.8.8?

systemctl status systemd-resolved.service ● systemd-resolved.service - Network Name Resolution Loaded: loaded (/lib/systemd/system/systemd-resolved.service; disabled; vendor preset: enabled) Drop-In: /usr/lib/systemd/system/systemd-resolved.service.d └─resolvconf.conf Active: active (running) since Fri 2021-12-03 13:10:35 EET; 1min 11s ago

Note that Proxmox VE does not enable/starts the systemd-resolver by default but uses the standard resolver which goes solely through /etc/resolv.conf, did you start that manually?

What does resolvectl output?

 

[James2021]

Is network itself working, i.e., ping 8.8.8.8?



Note that Proxmox VE does not enable/starts the systemd-resolver by default but uses the standard resolver which goes solely through /etc/resolv.conf, did you start that manually?

What does resolvectl output?

Hi,

Yes the network is working:

root@proxmox:/etc# ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=112 time=96.7 ms
64 bytes from 8.8.8.8: icmp_seq=2 ttl=112 time=106 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=112 time=93.0 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=112 time=93.4 ms
64 bytes from 8.8.8.8: icmp_seq=5 ttl=112 time=89.8 ms
^C
--- 8.8.8.8 ping statistics ---
5 packets transmitted, 5 received, 0% packet loss, time 10ms
rtt min/avg/max/mdev = 89.822/95.886/106.419/5.705 ms

systemd-resolver was there I don't know, I just got the status of it as some people on support forums checked it.

here is the output for resolvectl

root@proxmox:/etc# resolvectl
Global
       LLMNR setting: yes
MulticastDNS setting: yes
  DNSOverTLS setting: no
      DNSSEC setting: allow-downgrade
    DNSSEC supported: yes
         DNS Servers: 1.1.1.1
                      8.8.8.8
Fallback DNS Servers: 8.8.4.4
          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 3 (vmbr0)
      Current Scopes: LLMNR/IPv4 LLMNR/IPv6
DefaultRoute setting: no
       LLMNR setting: yes
MulticastDNS setting: no
  DNSOverTLS setting: no
      DNSSEC setting: allow-downgrade
    DNSSEC supported: yes
lines 1-45

 

[Indirectelex]

Is network itself working, i.e., ping 8.8.8.8?



Note that Proxmox VE does not enable/starts the systemd-resolver by default but uses the standard resolver which goes solely through /etc/resolv.conf, did you start that manually?

What does resolvectl output?

To me it say :
resolvectl
Failed to get global data: Unit dbus-org.freedesktop.resolve1.service not found.

 

[baldfox]

To me it say :
resolvectl
Failed to get global data: Unit dbus-org.freedesktop.resolve1.service not found.

Having the exact same issue as of about 8 days ago. Did you ever get a fix for it? For me it feels like it's at the container level, but am unable to diagnose it further...

 

[Shunia Huang]

To me it say :
resolvectl
Failed to get global data: Unit dbus-org.freedesktop.resolve1.service not found.

@Indirectelex @baldfox try:

systemctl status systemd-resolved.service

, if it shows something like "xxx dead", you may need to

systemctl start systemd-resolved.service

.
I found this useful to me and it's from OP's description.

 

[mguilmot]

I understand this is an old topic, but I had the exact same issue, with the same behaviour:
In my case: Firewall was on, but nothing configured further. Setup a rule to allow outbound traffic and it worked after that.
Might some one in the future.