Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
tdk.co.jp
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-31 03:37:04 UTC · ↺ Refresh
MX Hostnames
- tdksf1.jp.tdk.com
- tdksf2.jp.tdk.com
MX Priorities
- tdksf1.jp.tdk.com: 30
- tdksf2.jp.tdk.com: 5
A / AAAA Records
No A/AAAA records found.
Mail Server IPs
- 210.161.158.221 ↩ tdksf1.jp.tdk.com
- 211.16.239.3 ↩ tdksf2.jp.tdk.com
SOA Record
Raw SOA
ns000.d-53.net dns-managers.iij.ad.jp 288 3600 600 604800 900
Primary NS (mname)
ns000.d-53.net
Admin Email (rname)
dns-managers@iij.ad.jp
Serial
288
Refresh
3600s
Retry
600s
Expire
604800s
Minimum TTL
900s
Nameservers (NS)
ns020-n11bap4sh9q5em0b.n.d-53.info
ns020-n11bap4sh9q5em0b.n.d-53.jp
ns020-n11bap4sh9q5em0b.n.d-53.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:18.182.88.44 ip4:210.161.158.221 ip4:211.16.239.3 ip4:202.238.239.239 include:_netblocks.eloqua.com -all
📊 DNS lookups: 1/10
✓ 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
selector1._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 ip4:18.182.88.44 ip4:210.161.158.221 ip4:211.16.239.3 ip4:202.238.239.239 include:_netblocks.eloqua.com -all
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