Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
heinz-krumme.de
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-04-04 02:31:05 UTC · ↺ Refresh
MX Hostnames
- as6.custdnw.net
- as6.mailrelaypro.net
MX Priorities
- as6.mailrelaypro.net: 20
- as6.custdnw.net: 10
A / AAAA Records
- 88.198.22.168 ↩ balancer1.hosts.page-tech.de
Mail Server IPs
- 193.24.239.61 ↩ as6.custdnw.net
- 193.24.239.51 ↩ as6.custdnw.net
SOA Record
Raw SOA
ns1020.ui-dns.biz hostmaster.1und1.com 2017060174 28800 7200 604800 600
Primary NS (mname)
ns1020.ui-dns.biz
Admin Email (rname)
hostmaster@1und1.com
Serial
2017060174
Refresh
28800s
Retry
7200s
Expire
604800s
Minimum TTL
600s
Nameservers (NS)
ns1018.ui-dns.de
ns1055.ui-dns.com
ns1020.ui-dns.biz
ns1106.ui-dns.org
SPF Record
✓ Strict (-all)
v=spf1 a mx a:as6.custdnw.net a:as6.mailrelaypro.net ip4:193.24.239.51 include:spf.protection.outlook.com -all
📊 DNS lookups: 5/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
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
2 records- SPFv=spf1 a mx a:as6.custdnw.net a:as6.mailrelaypro.net ip4:193.24.239.51 include:spf.protection.outlook.com -all
- _globalsign-domain-verification=ZqqdFooiWZUZk6fl4nr4BrnMJxglYZ6uDNA2if9Hhd
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