Domain Overview
DNS: ✓ 20d ago
Checker: ✓ 20d ago
gbvoip.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-05-21 07:09:50 UTC · ↺ Refresh
MX Hostnames
- gbvoip-com.mail.protection.outlook.com
MX Priorities
- gbvoip-com.mail.protection.outlook.com: 0
A / AAAA Records
- 208.91.197.27 (no PTR)
Mail Server IPs
- 52.101.50.10 ↩ mail-mw2pr02cu00502.inbound.protection.outlook.com
- 52.101.11.10 ↩ mail-sa9pr03cu00202.inbound.protection.outlook.com
- 52.101.194.17 ↩ mail-ch5pr02cu00401.inbound.protection.outlook.com
- 52.101.10.16 ↩ mail-bn6pr21cu00500.inbound.protection.outlook.com
- 2a01:111:f403:c902::6 ↩ mail-sj0pr21cu00106.inbound.protection.outlook.com
- 2a01:111:f403:c927:: ↩ mail-bn6pr21cu00500.inbound.protection.outlook.com
- 2a01:111:f403:c802:: ↩ mail-cy4pr03cu00100.inbound.protection.outlook.com
- 2a01:111:f403:c92c::4 ↩ mail-dm6pr05cu00404.inbound.protection.outlook.com
SOA Record
Raw SOA
ns1.domain.com dnsadmin.domain.com 126051214 10800 3600 604800 3600
Primary NS (mname)
ns1.domain.com
Admin Email (rname)
dnsadmin@domain.com
Serial
126051214
Refresh
10800s
Retry
3600s
Expire
604800s
Minimum TTL
3600s
Nameservers (NS)
ns1.domain.com
ns2.domain.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:sendgrid.net -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; rua=mailto:[email protected] fo=1
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected] fo=1
DKIM Selectors
✓ 5 found
selector1._domainkey
selector2._domainkey
dkim._domainkey
s1._domainkey
s2._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- brevo-code:173fe99054a264db4c8e893007a0d3ef
- SPFv=spf1 include:spf.protection.outlook.com include:sendgrid.net -all
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