Check-Host.cc

IP Address IPv4

65.21.252.29

Aggregated from public BGP, CT logs, our scan layer, honeypots and global probes.

Run a live full scan of 65.21.252.29

On-demand: ports, banners, TLS, tech-stack, subdomains and origin/IP-leak detection. Results are shared publicly for everyone to link to.

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ASN
AS24940
Hetzner Online
Country
FI
Finland
Reverse DNS
static.29.252.21.65.clients.your-server.de
PTR
Open Ports
2
Last scan

Autonomous System

ASN
AS Name
Hetzner Online
AS Type
RIR
RIPE NCC
Allocated
2002-06-03
Allocation status
Allocated

Geolocation

Country
FI · Finland
Continent
Europe
Source
MaxMind GeoLite2

Reverse DNS

Last seen
2026-05-27 14:29:10

Network

Prefix
RPKI

Open Ports

Port Proto Service Server Last seen
22 tcp ssh 2026-05-26 10:37:02.000
443 tcp https nginx/1.27.5 2026-05-27 03:15:55.000

TLS Certificates

Port 443 558cdb3334d8…
Subject: derivationmap.net
Issuer: E8
SANs: allofphysics.com, derivationmap.net, www.allofphysics.com, www.derivationmap.net
Valid 2026-05-02 11:07:44 → 2026-07-31 11:07:43

Tech Stack

Detected via Wappalyzer-style rules on the HTTP response body, headers, scripts and meta tags.

Origin / IP-Leak

USP

When a hostname is served behind a CDN (e.g. Cloudflare), the origin server can sometimes be identified by matching its TLS cert against the protected hostname. Findings shown here are heuristic candidates, not guarantees.

No origin-leak candidates for this IP

When this IP serves a TLS cert for a domain that fronts behind a CDN, that domain surfaces here as an origin-leak candidate with a confidence score.

Hosted Domains

4 domains resolve (A-record) to this IP.

Multi-Vantage Check

Reachability accrued passively from real user-triggered checks across our 65+ probe nodes. Run a live check to add fresh data.

ICMP responsive This IP replied to our global ICMP sweep — last confirmed 2026-08-05.

No accumulated reachability data yet

Reachability accrues from real user-triggered checks. Trigger a Ping or HTTP check from our 65+ probe nodes to contribute the first data point.

Web Pages

Port Page title Status Flags
443 Welcome to the Physics Derivation Graph 200

Threat Intelligence

No threat-intel matches

This IP doesn't appear in any of the feeds we mirror (Tor exits, FireHOL Level 1-3, Spamhaus DROP/EDROP, URLhaus, OpenPhish). Absence here doesn't prove the IP is clean — it just means none of our public-feed sources flag it.

Co-Hosted Domains

Domains this host references in its HTML AND whose DNS A/AAAA record resolves back to this IP — i.e. actually hosted here.

allofphysics.com DNS-confirmed

External References

Domains the body links to whose DNS does NOT resolve to this IP — usually CDN assets, embeds, or third-party services. Boilerplate (Google Fonts, jsDelivr, w3.org…) is already filtered.

github.com href · ×10
bl.ocks.org href · ×7
developer.mozilla.org href · ×3
www.d3indepth.com href · ×2
www.codexworld.com href · ×2
www.reddit.com href · ×2
en.wikipedia.org href · ×2
docs.mathjax.org href · ×2
www.kryogenix.org href · ×2
search.google.com href · ×1
csvbase.com href · ×1
css-tricks.com href · ×1
app.gitter.im href · ×1
groups.google.com href · ×1
analytics.google.com href · ×1
stackoverflow.com href · ×1
chartio.com href · ×1
d3js.org href · ×1
www.freelancer.com href · ×1

History

First observed
2026-05-26 10:36
Last observed
2026-05-27 03:15
Scan observations
6

The full change-log (ASN moves, cert rotations, port-state diffs) accumulates as our archives grow.