Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
excelsior.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-23 07:39:47 UTC · ↺ Refresh
MX Hostnames
- excelsior-com.mail.protection.outlook.com
MX Priorities
- excelsior-com.mail.protection.outlook.com: 0
A / AAAA Records
- 104.17.71.73 (no PTR)
Mail Server IPs
- 52.101.42.18 ↩ mail-co1pr03cu00302.inbound.protection.outlook.com
- 52.101.11.15 ↩ mail-sa9pr02cu00207.inbound.protection.outlook.com
- 52.101.50.13 ↩ mail-mw2pr02cu00605.inbound.protection.outlook.com
- 52.101.11.3 ↩ mail-sn1pr0501cu00103.inbound.protection.outlook.com
- 2a01:111:f403:f90f::1 ↩ mail-sa9pr04cu00201.inbound.protection.outlook.com
- 2a01:111:f403:f804::3 ↩ mail-co1pr03cu00403.inbound.protection.outlook.com
- 2a01:111:f403:c927:: ↩ mail-bn6pr21cu00500.inbound.protection.outlook.com
- 2a01:111:f403:f902:: ↩ mail-bl2pr04cu00100.inbound.protection.outlook.com
SOA Record
Raw SOA
iris.ns.cloudflare.com dns.cloudflare.com 2398902818 10000 2400 604800 1800
Primary NS (mname)
iris.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2398902818
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
iris.ns.cloudflare.com
jack.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:spf.mandrillapp.com include:sky-dalrel-eml.iscorp.com include:skyspfguest.iscorp.com include:_spf.smtp.com -all
📊 DNS lookups: 5/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
⚠ No aggregate reports (rua= not set)
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 392 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
1 record- SPFv=spf1 include:spf.protection.outlook.com include:spf.mandrillapp.com include:sky-dalrel-eml.iscorp.com include:skyspfguest.iscorp.com include:_spf.smtp.com -all
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