Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
gfz-potsdam.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-02 03:17:06 UTC · ↺ Refresh
MX Hostnames
- a1791.mx.srv.dfn.de
- b1791.mx.srv.dfn.de
- c1791.mx.srv.dfn.de
MX Priorities
- b1791.mx.srv.dfn.de: 10
- c1791.mx.srv.dfn.de: 10
- a1791.mx.srv.dfn.de: 10
A / AAAA Records
- 139.17.229.15 ↩ gfz.de
Mail Server IPs
- 194.95.234.122 ↩ b1791.mx.srv.dfn.de
- 194.95.238.122 ↩ c1791.mx.srv.dfn.de
- 194.95.232.122 ↩ a1791.mx.srv.dfn.de
SOA Record
Raw SOA
zrt7b.gfz-potsdam.de its-ddi.gfz.de 2026033100 14400 3600 2592000 3600
Primary NS (mname)
zrt7b.gfz-potsdam.de
Admin Email (rname)
its-ddi@gfz.de
Serial
2026033100
Refresh
14400s
Retry
3600s
Expire
2592000s
Minimum TTL
3600s
Nameservers (NS)
ns.tu-berlin.de
zrt7b.gfz-potsdam.de
SPF Record
✓ Soft Fail (~all)
v=spf1 a:mail.gfz-potsdam.de a:otc-de-spf.mms.t-systems-service.com a:gfz-potsdam.managed-otrs.com ~all
📊 DNS lookups: 3/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine;
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 1 found
mail._domainkey
✓ Public key: 392 chars (valid)
✓ DKIM properly configured for selector: mail
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
9 records- ZOOM_verify_CrllNFoaSz-ueCpdG5kw5Q
- apple-domain-verification=ccIO5azzaBaa6TcV
- MS=05F96486DA61AEC028E58EB3C15EDE435221E370
- brevo-code:6fad695b8997745705f7bded854ca36f
- google-site-verification=RvjA1HesvuxNyikUZSDgH5E0TPFVW7CSxArTjUrBLV8
- google-site-verification=gbS63fzs8bE6n0poYa1SDdFbwQm9V685MzGsLB54MX8
- SPFv=spf1 a:mail.gfz-potsdam.de a:otc-de-spf.mms.t-systems-service.com a:gfz-potsdam.managed-otrs.com ~all
- HARICA-V6Apl9oRFGtG4wdhwPJ
- HARICA-kCGm3uNXt57A201dL8P
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