IPv6
Measured 2026-11-04 13:03 UTC · aaaa.botWebsite, mail and DNS all work over IPv6.
The published IPv6 address accepted a connection when we tried it.
- ✓ cra.cz answers (1 of 1 addresses)
- ✓ www.cra.cz answers (1 of 1)
- ✓ Mail: 1 of 1 servers have IPv6
- ✓ Nameservers: 3 of 3 have IPv6
Details: published addresses and what answered
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 403.
| Name | Published address (AAAA) | Answers when we connect |
|---|---|---|
| cra.cz | Published2a02:a40:200:3955::78 | Answers when we connect✓ answers on 443 |
| www.cra.cz | Published2a02:a40:200:3955::78 | Answers when we connect✓ answers on 443 |
Publishedcra-cz.mail.protection.outlook.com | Answers when we connect✓ has IPv6 | |
| Nameservers | Publishedns.bluetone.czns1.bluetone.czns2.bluetone.cz | Answers when we connect✓ has IPv6✓ has IPv6✓ has IPv6 |
Lineage
Our records: May 27, 2009 → Nov 4, 2026Oldest registry snapshot we hold: 2025 · 1 renewal on record. These dates are when our records begin, not when the domain was registered.
DNS provider
- bluetone.cz + cra.czMay 2009 – Apr 2014
- bluetone.czJun 2018 – Jun 2026
IPv6
- IPv6published, and answeringFirst measured Nov 2026
What changed
- IPv6 first measured: published, and answering on Nov 4, 2026cra.cz has 1 IPv6 address. Grade A. Measured by aaaa.bot, 2026-11-04 13:02 UTC. No earlier IPv6 record is held, so this is not a "gained" date.
- Renewed +1 year between Aug 7, 2025 and Oct 6, 2025Expiry moved from 2025-10-12 to 2026-10-12.
- DNS moved to bluetone.cz between Apr 25, 2014 and Jun 30, 2018ns.bluetone.cz, ns.cra.cz, ns1.bluetone.cz → ns.bluetone.cz, ns1.bluetone.cz, ns2.bluetone.cz. Old set last seen in WHOIS on 2014-04-25; new set first seen in WHOIS on 2018-06-30.
Solid bar: the stretch we observed that name. Dot: a single sighting. Dotted line: no record between sightings of the same name. Nothing is drawn between different names.
Registrar and renewals: 13 WHOIS/RDAP snapshots, 2025-05-15 to 2026-05-11 (ledger built 2026-09-27). Every renewal
DNS provider, WHOIS snapshots: 49 WHOIS/RDAP snapshots that listed nameservers, 2009-05-27 to 2026-06-21 (who.is archive). Both sources feed one row per provider (hover a bar to see which); a change is placed between the nearest observations on either side, and where the two sources disagree, both are listed under What changed.
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Explore related
Registered in 1997 — the same year as google.com, facebook.com and mail.ru.