Has an IPv4 address but no IPv6 (AAAA) record. IPv6-only visitors can't reach it directly.
D
IPv6 readiness
The website has no IPv6.
Website over IPv6 ad-tech.ru has no AAAA record.
no
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record.
mx.ad-tech.ru ✗
no
Nameservers have IPv6 No nameserver has an AAAA record — an IPv6-only resolver can't reach this domain's DNS.
ns3.ad-tech.ru ✗ns2.ad-tech.ru ✗
no
What's keeping ad-tech.ru from an A
Give ad-tech.ru an IPv6 address Ask your hosting provider for the site's IPv6 address (or the hostname to point at), then publish it as an AAAA record. If your host doesn't offer IPv6, a proxy that does can sit in front. How to add an AAAA record
Mail servers without IPv6 mx.ad-tech.ru has no AAAA record, so mail from IPv6-only servers can't reach it directly. If a provider runs your mail, that's their setting; if you run it, add AAAA records for these hosts.
Nameservers without IPv6 ns3.ad-tech.ru, ns2.ad-tech.ru all have no AAAA record, so a resolver that only speaks IPv6 can't look your domain up. Most DNS providers offer IPv6 nameservers; ask yours, or move DNS to one that does.
Visitors on IPv6-only networks (many mobile carriers) can still reach it, but only through a translator their carrier runs (NAT64). The site itself has no IPv6 address — and you can't make one up from the IPv4. Why some hosts don't offer it
Copy the evidence— a citation-ready record of this measurement