Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
rationalkorea.co.kr
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-26 18:16:22 UTC · ↺ Refresh
MX Hostnames
- gwmail.ktbizoffice.com
MX Priorities
- gwmail.ktbizoffice.com: 10
A / AAAA Records
- 203.245.44.93 (no PTR)
Mail Server IPs
- 211.62.105.162 ↩ gwspam2.ktbizoffice.com
- 211.62.105.163 ↩ gwspam3.ktbizoffice.com
- 211.62.105.164 ↩ gwspam4.ktbizoffice.com
SOA Record
Raw SOA
rationalkorea.co.kr postmaster.rationalkorea.co.kr 20200731 10800 3600 3600000 43200
Primary NS (mname)
rationalkorea.co.kr
Admin Email (rname)
postmaster@rationalkorea.co.kr
Serial
20200731
Refresh
10800s
Retry
3600s
Expire
3600000s
Minimum TTL
43200s
Nameservers (NS)
ns2.cafe24.com
ns1.cafe24.co.kr
ns1.cafe24.com
ns2.cafe24.co.kr
SPF Record
✓ Soft Fail (~all)
v=spf1 include:gwspf.ktbizoffice.com ~all
📊 DNS lookups: 1/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ MissingNo DMARC record — emails cannot be rejected on auth failure.
DKIM Selectors
✓ 13 found
google._domainkey
selector1._domainkey
selector2._domainkey
default._domainkey
mail._domainkey
dkim._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
zoho._domainkey
sendgrid._domainkey
mxvault._domainkey
amazonses._domainkey
⚠ Public key (p=) missing in DKIM record for selector google.
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
1 record- SPFv=spf1 include:gwspf.ktbizoffice.com ~all
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