Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
costello.ca
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-22 06:13:24 UTC · ↺ Refresh
MX Hostnames
- mail.rcsigs.ca
MX Priorities
- mail.rcsigs.ca: 10
A / AAAA Records
- 192.211.125.92 ↩ superml370.rcsigs.ca
Mail Server IPs
- 192.211.125.92 ↩ superml370.rcsigs.ca
SOA Record
Raw SOA
ns3.rcsigs.ca sean.costello.ca 2024120502 21600 3600 604800 86400
Primary NS (mname)
ns3.rcsigs.ca
Admin Email (rname)
sean@costello.ca
Serial
2024120502
Refresh
21600s
Retry
3600s
Expire
604800s
Minimum TTL
86400s
Nameservers (NS)
ns2.rcsigs.ca
ns3.rcsigs.ca
ns4.rcsigs.ca
SPF Record
✗ MissingNo SPF record — domain is unprotected against spoofing.
⚠ No SPF record found. Email servers cannot verify authorized senders.
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
No TXT records found.
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