Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
castel.com.mx
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-21 22:21:35 UTC · ↺ Refresh
MX Hostnames
- castel-com-mx.mail.protection.outlook.com
MX Priorities
- castel-com-mx.mail.protection.outlook.com: 0
A / AAAA Records
- 172.67.196.79 (no PTR)
- 104.21.65.252 (no PTR)
- 2606:4700:3030::ac43:c44f
- 2606:4700:3032::6815:41fc
Mail Server IPs
- 52.101.42.16 ↩ mail-co1pr05cu00300.inbound.protection.outlook.com
- 52.101.10.18 ↩ mail-bn8pr05cu00302.inbound.protection.outlook.com
- 52.101.41.58 ↩ mail-sj0pr02cu00102.inbound.protection.outlook.com
- 52.101.41.180 ↩ mail-byapr04cu00204.inbound.protection.outlook.com
- 2a01:111:f403:f910:: ↩ mail-cy5pr03cu00300.inbound.protection.outlook.com
- 2a01:111:f403:c92c::4 ↩ mail-dm6pr05cu00404.inbound.protection.outlook.com
- 2a01:111:f403:c946::2 ↩ mail-ch4pr04cu00102.inbound.protection.outlook.com
- 2a01:111:f403:f913::1 ↩ mail-cy5pr05cu00101.inbound.protection.outlook.com
SOA Record
Raw SOA
guy.ns.cloudflare.com dns.cloudflare.com 2397986456 10000 2400 604800 1800
Primary NS (mname)
guy.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2397986456
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
treasure.ns.cloudflare.com
guy.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 include:spf.protection.outlook.com include:o2.o1.email.spacemail.mx include:sendgrid.net ip4:201.175.5.115 ip4:167.89.7.65 -all
📊 DNS lookups: 4/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1; p=quarantine; rua=mailto:[email protected]; ruf=mailto:[email protected];
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 4 found
selector1._domainkey
selector2._domainkey
s1._domainkey
s2._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
2 records- 4z8nPBGf
- SPFv=spf1 include:spf.protection.outlook.com include:o2.o1.email.spacemail.mx include:sendgrid.net ip4:201.175.5.115 ip4:167.89.7.65 -all
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