Hoster's DNS is working strangely or not working, how to check?

Question

System administration

The hoster provides its own DNS servers to the server. There are also public Google 8.8.8.8 The point
is that on the physical server with the hoster's DNS, the address resolution works, and when I install the KVM / QEMU virtual machine with the same hoster's DNS, the ping passes, but the site addresses do not resolve.

When I just change to public Google 8.8.8.8 - everything works as expected. I change back to the hoster's DNS, reboot - the ping goes on, there is no resolution. How to check what is the plug?

Hoster online net their 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)

I register DNS in /etc/resolvconf/resolv.conf.d/base

Answer 1

From the outside, this DNS does not respond to nslookup. Either they have specific restrictions on which networks to work from (which is logical in principle), and the physical server gets into the allowed networks, but the virtual one does not, or it works only after a rain on Thursday

Answer 2

DNS can work both over UDP (the traditional way) and over TCP (a new way that resists some types of attacks). Ask the hoster how about this?