Yes — lightrail.quest has IPv6.

Has both IPv4 (A) and IPv6 (AAAA) addresses.

IPv6 readiness

Works over IPv6, with one gap: its mail servers lack IPv6.

Website over IPv6 lightrail.quest has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3037::6815:2563 answers · 443✓ 2606:4700:3037::ac43:cf11 answers · 443	yes
www over IPv6 www.lightrail.quest has 2 IPv6 addresses and answers on every one we tested. ✓ 2606:4700:3037::ac43:cf11 answers · 443✓ 2606:4700:3037::6815:2563 answers · 443	yes
Mail servers (MX) have IPv6 None of the mail servers has an AAAA record. eforward1.registrar-servers.com ✗eforward2.registrar-servers.com ✗eforward3.registrar-servers.com ✗eforward4.registrar-servers.com ✗eforward5.registrar-servers.com ✗	no
Nameservers have IPv6 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up. brit.ns.cloudflare.com ✓patrick.ns.cloudflare.com ✓	yes

HTTPS over IPv6 · not part of the grade yet
Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.

https://lightrail.quest/ via 2606:4700:3037::6815:2563 → 302https://lightrail.cloudflareaccess.com/cdn-cgi/access/login/lightrail.quest?kid=52c9798f0ca1df6c0fd8e80afbdee4b70ab439e63cbd930d7578c4ede789f329&meta=eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6ImEyOGQzNDc0NzNhMzBmMDgwZmRmZDdjMTc2Mjk1YThiMmQ0Mjc5OTRjOWM5MzI2NGYxODIzYTkwZGEwMWU3NTgifQ.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.V9NWnjRFcUE4YMvBtWAtFehhWGeXTNrwQPFSDH8l3u6OjmRYR5pS_-2DNgYOC66XWWMZTv-k1cqIQYuHxPU8gJEk7CyMd9KLGNyqVXNEcPNaSpUW962auLlBpg2L4vDg02SS6wZz1GauWtaxgrrFgcO9Lg8FSPOpgP85RPIVgJuVlpTA1lXIR3zhaoRtdokAsQGgIkYLvdq5nl-5u9DzkDedjdhyl0IyR8ooAdVM2z7md66GWUuJgzlUnE2HTb6lIIhY-C3x-yF6e9U8IBwpIUqULxA3ejUYZnvDAgnS0pvnmlNibVRU_I0bga7BUBDDDW6WMT6WXVr51fGMhMeCiw&redirect_url=%2F via 2606:4700:300a::6813:c21d → 200

works

What's keeping lightrail.quest from an A

Mail servers without IPv6
eforward1.registrar-servers.com, eforward2.registrar-servers.com, eforward3.registrar-servers.com, eforward4.registrar-servers.com, eforward5.registrar-servers.com have no AAAA record, so mail from IPv6-only servers can't reach them directly. If a provider runs your mail, that's their setting; if you run it, add AAAA records for these hosts.

Check again

lightrail.quest Has IPv6

A (IPv4)	172.67.207.17 104.21.37.99
AAAA (IPv6)	2606:4700:3037::6815:2563 2606:4700:3037::ac43:cf11

www.lightrail.quest Has IPv6

A (IPv4)	104.21.37.99 172.67.207.17
AAAA (IPv6)	2606:4700:3037::ac43:cf11 2606:4700:3037::6815:2563

Browsers on dual-stack networks will usually pick IPv6 here (the "Happy Eyeballs" algorithm races both and prefers v6).

Copy the evidence — a citation-ready record of this measurement

IPv6 measurement: lightrail.quest
Measured 2026-11-04 06:56:30 UTC by aaaa.bot (one server on Fly.io, region iad)

A (IPv4):    172.67.207.17, 104.21.37.99
AAAA (IPv6): 2606:4700:3037::6815:2563, 2606:4700:3037::ac43:cf11
www AAAA:    2606:4700:3037::ac43:cf11, 2606:4700:3037::6815:2563

Readiness grade B: Works over IPv6, with one gap: its mail servers lack IPv6.
- Website over IPv6: lightrail.quest has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3037::6815:2563: answers (TCP 443)
    2606:4700:3037::ac43:cf11: answers (TCP 443)
- www over IPv6: www.lightrail.quest has 2 IPv6 addresses and answers on every one we tested.
    2606:4700:3037::ac43:cf11: answers (TCP 443)
    2606:4700:3037::6815:2563: answers (TCP 443)
- Mail servers (MX) have IPv6: None of the mail servers has an AAAA record.
- Nameservers have IPv6: 2 of 2 nameservers checked have an AAAA record, so IPv6-only resolvers can look the domain up.

Reachability = a TCP connection opened on port 443 (or 80).

HTTPS over IPv6 (not graded): Loads over IPv6 with a valid certificate after 1 redirect: HTTP 200.
    https://lightrail.quest/ via 2606:4700:3037::6815:2563 -> HTTP 302, certificate: valid
    https://lightrail.cloudflareaccess.com/cdn-cgi/access/login/lightrail.quest?kid=52c9798f0ca1df6c0fd8e80afbdee4b70ab439e63cbd930d7578c4ede789f329&meta=eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiIsImtpZCI6ImEyOGQzNDc0NzNhMzBmMDgwZmRmZDdjMTc2Mjk1YThiMmQ0Mjc5OTRjOWM5MzI2NGYxODIzYTkwZGEwMWU3NTgifQ.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.V9NWnjRFcUE4YMvBtWAtFehhWGeXTNrwQPFSDH8l3u6OjmRYR5pS_-2DNgYOC66XWWMZTv-k1cqIQYuHxPU8gJEk7CyMd9KLGNyqVXNEcPNaSpUW962auLlBpg2L4vDg02SS6wZz1GauWtaxgrrFgcO9Lg8FSPOpgP85RPIVgJuVlpTA1lXIR3zhaoRtdokAsQGgIkYLvdq5nl-5u9DzkDedjdhyl0IyR8ooAdVM2z7md66GWUuJgzlUnE2HTb6lIIhY-C3x-yF6e9U8IBwpIUqULxA3ejUYZnvDAgnS0pvnmlNibVRU_I0bga7BUBDDDW6WMT6WXVr51fGMhMeCiw&redirect_url=%2F via 2606:4700:300a::6813:c21d -> HTTP 200, certificate: valid
DNS answers via DNS-over-HTTPS (Cloudflare). Method: https://aaaa.bot/method
Permanent link: https://aaaa.bot/r/A9-et8HOS3

Permanent link: aaaa.bot/r/A9-et8HOS3 · How we measure

Checked 2026-11-04 06:56:30 UTC. Full DNS report: dns.pizza/domain/lightrail.quest · Age, certificate and blocklists: how.is/lightrail.quest · JSON: /api/v1/lightrail.quest