Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
b-tu.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-04-02 16:40:42 UTC · ↺ Refresh
MX Hostnames
- smtp-3.b-tu.de
- smtp-4.b-tu.de
MX Priorities
- smtp-3.b-tu.de: 10
- smtp-4.b-tu.de: 20
A / AAAA Records
No A/AAAA records found.
Mail Server IPs
- 141.43.208.13 ↩ smtp-3.b-tu.de
- 141.43.208.14 ↩ smtp-4.b-tu.de
SOA Record
Raw SOA
dns.rz.tu-cottbus.de hostmaster.tu-cottbus.de 2026032701 21600 3600 1814400 3600
Primary NS (mname)
dns.rz.tu-cottbus.de
Admin Email (rname)
hostmaster@tu-cottbus.de
Serial
2026032701
Refresh
21600s
Retry
3600s
Expire
1814400s
Minimum TTL
3600s
Nameservers (NS)
deneb.dfn.de
math-s.math.tu-cottbus.de
dns.rz.tu-cottbus.de
dns2.sbone.tu-cottbus.de
SPF Record
✓ Soft Fail (~all)
v=spf1 ip4:141.43.208.11 ip4:141.43.208.12 ip4:141.43.208.13 ip4:141.43.208.14 ip4:141.43.208.15 ip4:141.43.208.19/32 ip4:141.43.7.73/32 ip4:141.43.7.75/32 ip4:141.43.208.213 ip4:141.43.208.214 ip4:141.43.208.219 ?all
📊 DNS lookups: 0/10
? Neutral (?all) — no enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]; fo=1;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✗ None detectedNo DKIM records found for common selectors — your provider may use a custom selector name.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 ip4:141.43.208.11 ip4:141.43.208.12 ip4:141.43.208.13 ip4:141.43.208.14 ip4:141.43.208.15 ip4:141.43.208.19/32 ip4:141.43.7.73/32 ip4:141.43.7.75/32 ip4:141.43.208.213 ip4:141.43.208.214 ip4:141.43.208.219 ?all
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