Publishes IPv6 but doesn't answer on it — worse than having none.
Website over IPv6 sweb.ru has an AAAA record, but nothing answered on ports 443 or 80. IPv6 visitors wait for a timeout before falling back to IPv4.
✗ 2a02:408:7722:41:77:222:41:15 no answer
broken
www over IPv6 www.sweb.ru has no AAAA record.
no
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record.
mx.runity.ru ✗
no
Nameservers have IPv6 3 of 3 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.
ns4.sweb.ru ✓ns2.sweb.ru ✓ns1.sweb.ru ✓
yes
What's keeping sweb.ru from an A
Fix or remove the AAAA record for sweb.ru Something published an IPv6 address but nothing answers on it, so IPv6 visitors wait for a timeout first. Either make the server listen on IPv6 (and allow ports 443/80 through its firewall), or delete the AAAA record until it does.
Add IPv6 for www.sweb.ru www.sweb.ru has no AAAA record. Get www's IPv6 address from whoever hosts www and add it as an AAAA record. If the same server already serves both names (and its certificate covers www), you can reuse sweb.ru's AAAA record(s) for www. How to add an AAAA record
Mail servers without IPv6 mx.runity.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.