Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
zub.edu.pl
Disposable
✓ Yes
Unknown
⚠ Yes
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-09-05 04:02:04 UTC · ↺ Refresh
MX Hostnames
- mail.mtempmail.com
MX Priorities
- mail.mtempmail.com: 10
A / AAAA Records
- 89.117.63.226 ↩ vmi3543028.contaboserver.net
Mail Server IPs
- 89.117.63.226 ↩ vmi3543028.contaboserver.net
SOA Record
Raw SOA
dns10.ovh.ca tech.ovh.net 2088161709 86400 3600 3600000 60
Primary NS (mname)
dns10.ovh.ca
Admin Email (rname)
tech@ovh.net
Serial
2088161709
Refresh
86400s
Retry
3600s
Expire
3600000s
Minimum TTL
60s
Nameservers (NS)
ns10.ovh.ca
dns10.ovh.ca
SPF Record
✓ Strict (-all)
v=spf1 +a +mx -all
📊 DNS lookups: 2/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
~ Quarantine
v=DMARC1;p=quarantine;rua=mailto:[email protected]
~ Quarantine — good protection (failing mail goes to spam)
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 1 found
default._domainkey
✓ Public key: 30 chars (valid)
⚠ Public key too short (30 chars) — DKIM may be invalid.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 +a +mx -all
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