clseifert.dk

📜 Historical scan 2026-09-03 20:51:53 · ← Latest scan

⬇ Zone File 📜 Timeline & History ⚡ Scan Now

clseifert.dk is a .dk domain served by 2 nameservers (lucy.ns.cloudflare.com, sam.ns.cloudflare.com). It was registered on 12 February 1997 (WHOIS) and was already in the .dk zone when our tracking began on 16 June 2026. Its website address 104.21.33.73 is hosted by Cloudflare, Inc. (AS13335). Mail is handled by mx.spamfilter.io. The zone is not DNSSEC-signed, publishes a DMARC policy and is reachable over IPv6. Below are all of its DNS records from this scan: nameservers, A/AAAA, MX, TXT, SPF, DMARC, CAA, TLSA/DANE, MTA-STS, SRV and more.

🖥️ Nameservers#

2 records 37ms

Nameserver	IP addresses	PTR	ASN / ISP
lucy.ns.cloudflare.com	108.162.192.133 172.64.32.133 173.245.58.133 2606:4700:50::adf5:3a85 2803:f800:50::6ca2:c085 2a06:98c1:50::ac40:2085	lucy.ns.cloudflare.com lucy.ns.cloudflare.com lucy.ns.cloudflare.com lucy.ns.cloudflare.com lucy.ns.cloudflare.com lucy.ns.cloudflare.com	AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc.
sam.ns.cloudflare.com	108.162.193.141 172.64.33.141 173.245.59.141 2606:4700:58::adf5:3b8d 2803:f800:50::6ca2:c18d 2a06:98c1:50::ac40:218d	sam.ns.cloudflare.com sam.ns.cloudflare.com sam.ns.cloudflare.com sam.ns.cloudflare.com sam.ns.cloudflare.com sam.ns.cloudflare.com	AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc. AS13335 Cloudflare, Inc.

🌍 A Records#

2 records 46ms

IP	TTL	PTR	ASN	ISP / Org	CIDR	Country	City
104.21.33.73	300s	—	AS13335	Cloudflare, Inc.	104.21.0.0/17	—	—
172.67.159.252	300s	—	AS13335	Cloudflare, Inc.	172.67.128.0/17	—	—

📧 MX Records#

1 records 38ms

Priority	TTL	Mail Server	IP addresses	PTR	ASN
10	300s	mx.spamfilter.io	46.36.212.34 46.36.212.36 46.36.212.37 46.36.212.38 89.188.78.64 89.188.78.65 89.188.78.66 94.231.106.12	node4.spamfilter.io node8.spamfilter.io node6.spamfilter.io node7.spamfilter.io node3.spamfilter.io node9.spamfilter.io node10.spamfilter.io node2.spamfilter.io	AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S AS48854 team.blue Denmark A/S

📧 Autodiscover / Autoconfig#

Service	CNAME / IP
🔷 Autodiscover	autodiscoverredirect.webexchange.nu → 212.237.249.80

🔷 AAAA Records (IPv6)#

2 records 43ms

IPv6 Address	TTL	PTR	ASN	ISP / Org	CIDR	Country	City
2606:4700:3032::ac43:9ffc	300s	—	AS13335	Cloudflare, Inc.	2606:4700:3000:0:0:0:0:0/42	—	—
2606:4700:3034::6815:2149	300s	—	AS13335	Cloudflare, Inc.	2606:4700:3000:0:0:0:0:0/42	—	—

🔐 HTTPS Records#

1 records 32ms

Priority	Target	SvcParams
1 service	.	alpn="h3,h2" ipv4hint=104.21.33.73,172.67.159.252 ech=AEX+DQBBZgAgACAFlsnR4iFUycJddVvSQ+8Vbmk6j1KyPXsgsg3EHOE1FQAEAAEAAQASY2xvdWRmbGFyZS1lY2guY29tAAA= ipv6hint=2606:4700:3032::ac43:9ffc,2606:4700:3034::6815:2149

📝 TXT Records#

2 records 194ms

TXT Record
v=DKIM1; k=rsa; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCrLHiExVd55zd/IQ/J/mRwSRMAocV/hMB3jXwaHH36d9NaVynQFYV8NaWi69c1veUtRzGt7yAioXqLj7Z4TeEUoOLgrKsn8YnckGs9i3B3tVFB+Ch/4mPhXWiNfNdynHWBcPcbJ8kjEQ2U8y78dHZj1YeRXXVvWob2OaKynO8/lQIDAQAB;
v=spf1 ip4:5.79.99.192/26 include:spf.scannet.dk include:mail.zendesk.com ip4:89.188.72.211 ~all

✉️ SPF#

Policy	Record (clseifert.dk)
~all (soft fail)	v=spf1 ip4:5.79.99.192/26 include:spf.scannet.dk include:mail.zendesk.com ip4:89.188.72.211 ~all

📨 DMARC#

Policy	Record (_dmarc.clseifert.dk)
p=quarantine	v=DMARC1; p=quarantine; pct=100; aspf=s; adkim=s

📬 MTA-STS#

✗ No MTA-STS policy — SMTP TLS not enforced

📈 TLSRPT#

✗ No TLSRPT record — no SMTP TLS failure reporting

📜 CAA Records#

✗ No CAA records — any CA may issue certificates

🧩 Web & zone#

latest probe, not this scan · checked 2026-10-19 00:33:36

www	104.21.33.73 172.67.159.252 2606:4700:3032::ac43:9ffc 2606:4700:3034::6815:2149 (AS13335) (address records, no CNAME)
www vs bare domain	Same network clseifert.dk: 104.21.33.73 172.67.159.252 2606:4700:3032::ac43:9ffc 2606:4700:3034::6815:2149 (AS13335) www.clseifert.dk: 104.21.33.73 172.67.159.252 2606:4700:3032::ac43:9ffc 2606:4700:3034::6815:2149 (AS13335)
Wildcard	No

✍️ DKIM keys#

2 found

Selector	CNAME	Key
s1	s1.domainkey.u16044467.wl218.sendgrid.net	RSA · ~1024 bit below 2048 bit
s2	s2.domainkey.u16044467.wl218.sendgrid.net	RSA · ~1024 bit below 2048 bit

DKIM selectors can't be listed, so we check the common ones (Microsoft 365, Google, Mailchimp, SendGrid, generic). Keys under other selectors aren't shown.

🔎 SPF check#

zone-wide SPF report

DNS lookups: 4/10 · policy: ~all

No problems found

🔗 TLSA / DANE#

1 records 63ms

Service / Owner	Type	Cert association
SMTP _25._tcp.mx.spamfilter.io	DANE-EE · SPKI · SHA-256	9A25F05F2E322DABDCC9B7A06AB47A2D…

🔐 DNSSEC#

72ms

Check	Result
Validation Status	🔓 Insecure
AD Flag (resolver validates)	✗ Not set
DS Record	✗ Not found
DNSKEY Record	✗ Not found
Flags	unsigned answer

🏷️ SOA#

0ms

Field	Value
Serial	2412367856
Primary NS (MNAME)	lucy.ns.cloudflare.com
Responsible (RNAME)	dns@cloudflare.com
Refresh	10000s
Retry	2400s
Expire	604800s
Minimum (neg-cache TTL)	1800s

📋 Registration#

WHOIS fetched 2026-10-19 00:59:23

Field	Value
Registrar	Punktum dk A/S (direct)
Registered	1997-02-12
Expires	2027-03-31 (162d)

🔗 Same registrant#

7 domains

Other .dk domains whose WHOIS registrant has the same name and postal address. Matched on a keyed hash: the registrant's details are not stored or shown. Covers only domains whose WHOIS we have fetched (refreshed about monthly).

Domain	Registrar
aje.dk	Punktum dk A/S (direct)
ajeriksen.dk	Punktum dk A/S (direct)
blackboxapp.dk	Punktum dk A/S (direct)
insignias.dk	Simply.com A/S
seifertprivilege.dk	Punktum dk A/S (direct)
skoletroeje.dk	Punktum dk A/S (direct)
studentrose.dk	Simply.com A/S

📋 WHOIS#

⏱️ Lookup Timing#

37ms

46ms

38ms

AAAA

43ms

TXT

194ms

CAA

42ms

HTTPS

32ms

TLSA

63ms

SOA

0ms

MTA-STS

55ms

DNSSEC

72ms

SRV

74ms

Total

671ms

🕐 Scan History#

Scanned At	Duration	Records	DNSSEC
2026-10-19 00:33:36	2807ms	2 NS 2 A 1 MX	🔓 Insecure
2026-10-16 22:10:22	1322ms	2 NS 2 A 1 MX	🔓 Insecure
2026-10-08 07:45:48	820ms	2 NS 2 A 1 MX	🔓 Insecure
2026-09-30 03:56:22	599ms	2 NS 2 A 1 MX	🔓 Insecure
2026-09-24 21:41:44	746ms	2 NS 2 A 1 MX	🔓 Insecure
2026-09-03 20:51:53 shown	671ms	2 NS 2 A 1 MX	🔓 Insecure
2026-08-28 09:52:53	682ms	2 NS 2 A 1 MX	🔓 Insecure
2026-08-17 13:16:01	9331ms	2 NS 2 A 1 MX	🔓 Insecure
2026-08-16 09:54:16	5852ms	2 NS 2 A 1 MX	🔓 Insecure
2026-07-29 12:57:14	3190ms	2 NS 2 A 1 MX	🔓 Insecure
2026-06-24 17:49:01	1935ms	2 NS 2 A 1 MX	🔓 Insecure
2026-06-24 05:11:04	1006ms	2 NS 2 A 1 MX	❓ Unknown
2026-06-23 13:52:11	1040ms	2 NS 2 A 1 MX	🔓 Insecure
2026-06-16 21:25:41	673ms	2 NS 2 A 1 MX	🔓 Insecure