DNS Hoster工作异常或不起作用，如何检查？

Question

Hoster together with the server provides its own DNS servers. On the physical server with the host's DNS the resolver works, but when I install the KVM / QEMU virtual server with the same DNS host - the ping passes, and the addresses of the sites do not resolved.

When I just change to public Google 8.8.8.8 - everything works as expected. I change back to the DNS host, reboot - the ping is on, there is no resolve. How can I check the problem?

Hoster online net - DNS 62.210.16.(6/7)

#mtr google.com
Failed to resolve host: Temporary failure in name resolution

# traceroute google.com
google.com: Temporary failure in name resolution
Cannot handle "host" cmdline arg `google.com' on position 1 (argc 1)


# mtr 62.210.16.6 --report
Start: Mon Jul 30 21:19:38 2018
HOST: hp1                         Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 163.172.216.1              0.0%    10    0.6   0.6   0.5   0.8   0.0
  2.|-- 195.154.2.128              0.0%    10    0.4   0.6   0.4   0.7   0.0
  3.|-- 195.154.2.108              0.0%    10    1.0   1.0   0.9   1.2   0.0
  4.|-- 195.154.2.124              0.0%    10    0.7   0.7   0.7   0.8   0.0
  5.|-- 195.154.1.224              0.0%    10    0.7   0.6   0.6   0.7   0.0
  6.|-- 62.210.16.6                0.0%    10    0.3   0.4   0.3   0.4   0.0

With the dns hoster the traceroute 8.8.8.8 works, but for very long - 2-3 minutes.

# traceroute 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
 1  163.172.216.1 (163.172.216.1)  0.607 ms  0.955 ms  0.894 ms
 2  195.154.2.128 (195.154.2.128)  0.545 ms  0.487 ms 195.154.2.126 (195.154.2.126)  0.458 ms
 3  195.154.2.106 (195.154.2.106)  0.579 ms  0.770 ms  0.640 ms
 4  80.249.208.247 (80.249.208.247)  13.231 ms  13.352 ms  13.493 ms
 5  108.170.241.193 (108.170.241.193)  13.271 ms  13.367 ms  13.306 ms
 6  108.170.234.19 (108.170.234.19)  14.028 ms 216.239.50.197 (216.239.50.197)  14.305 ms 108.170.236.147 (108.170.236.147)  12.830 ms
 7  8.8.8.8 (8.8.8.8)  10.722 ms  10.799 ms  10.528 ms

Answer 1

First what is your hoster DNS address ( cat /etc/resolv.conf) ?

I think you need to check whether your hoster DNS provide reverse resolving try to do next steps:

• dig example.com @YOUR_HOSTER (IP or DNS name)
• if it return Blank or something wrong it seems that your hoster doesn't provide public reverse DNS lookup like google's 8.8.8.8 does.