Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rsp.de.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-04-02 10:26:00 UTC · ↺ Refresh
MX Hostnames
- rsp-de-com.mail.protection.outlook.com
MX Priorities
- rsp-de-com.mail.protection.outlook.com: 0
A / AAAA Records
- 212.97.109.170 ↩ w04.gbc.systems
Mail Server IPs
- 52.101.73.1 ↩ mail-am3pr04cu00501.inbound.protection.outlook.com
- 52.101.68.18 ↩ mail-db4pr02cu00302.inbound.protection.outlook.com
- 52.101.73.2 ↩ mail-as9pr07cu00302.inbound.protection.outlook.com
- 52.101.68.16 ↩ mail-db4pr02cu00400.inbound.protection.outlook.com
- 2a01:111:f403:ca04::2 ↩ mail-du2pr03cu00102.inbound.protection.outlook.com
- 2a01:111:f403:ca09::d ↩ mail-as9pr05cu01305.inbound.protection.outlook.com
- 2a01:111:f403:ca09::c ↩ mail-as8pr05cu00304.inbound.protection.outlook.com
- 2a01:111:f403:ca04::c ↩ mail-db9pr02cu00204.inbound.protection.outlook.com
SOA Record
Raw SOA
ns.gbc.systems support.gbc.net 2024100720 3600 900 1209600 300
Primary NS (mname)
ns.gbc.systems
Admin Email (rname)
support@gbc.net
Serial
2024100720
Refresh
3600s
Retry
900s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
ns.gbc.red
ns.gbc.jetzt
ns.gbc.systems
ns.gbc.green
ns.gbc.gmbh
SPF Record
✓ Strict (-all)
v=spf1 a ip4:212.97.96.0/19 include:spf.emailsignatures365.com include:spf.protection.outlook.com include:147232938.spf04.hubspotemail.net -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none;
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: selector1
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
2 records- SPFv=spf1 a ip4:212.97.96.0/19 include:spf.emailsignatures365.com include:spf.protection.outlook.com include:147232938.spf04.hubspotemail.net -all
- hubspot-developer-verification=NzIzMjQwODUtMTQ3My00MzQxLWFkZmMtYjE4MzcyMTBjNzBh
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