Hostname
f.cz
Last fetched
f.cz resolves to 1 IPv4 address operated by AS51400 in CZ. WHOIS lists registrar:reg-gransy as the registrar.
Nutrition Label
Resolution chain
f.cz resolves to 1 distinct IPv4 address via WhisperGraph DNS data. Each row links to the IP, prefix, and announcing ASN.
| IP | Prefix | ASN | Operator | Country |
|---|---|---|---|---|
| 77.87.240.99 | 77.87.240.0/21 | AS51400 | — | CZ |
WHOIS identity
- Registrar
- registrar:reg-gransy
- Organization
- spoje.net s.r.o.
- Contact emails
Subdomains
8 observed subdomains of f.cz.
Showing 4 of 8. View all subdomains →
Web-graph footprint
Distinct hostnames that link to or from f.cz in the public web crawl.
151 sites link to this hostname.
21 sites linked to from this hostname.
Sample inbound links
Threat posture
History
Mail and authentication
MX records
SPF policy
11 SPF mechanisms authorising senders for f.cz.
| Mechanism | Target |
|---|---|
| SPF_A | dev.spoje.net |
| SPF_A | iris.spoje.net |
| SPF_A | iris2.spoje.net |
| SPF_A | mail.mithrandir.cz |
| SPF_A | mail.spoje.net |
| SPF_A | mail2.spoje.net |
| SPF_A | registry.subreg.cz |
| SPF_A | smtp-out.spoje.net |
| SPF_A | smtp.spoje.net |
| SPF_INCLUDE | spf.protection.outlook.com |
| SPF_MX | f.cz |
Related pages
Pivot deeper into the graph from f.cz.
Cypher and MCP
Reproduce the resolution chain directly against graph.whisper.security:
MATCH (h:HOSTNAME {name: "f.cz"})-[:RESOLVES_TO]->(ip:IPV4)
-[:ANNOUNCED_BY]->(ap:ANNOUNCED_PREFIX)
-[:ROUTES]->(asn:ASN)-[:HAS_NAME]->(n:ASN_NAME)
RETURN ip.name AS ip, ap.name AS prefix, asn.name AS asn, n.name AS operator
LIMIT 20Or query Whisper from your own LLM workflow via the Whisper MCP server.