Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
coreserver.jp
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-26 17:20:38 UTC · ↺ Refresh
MX Hostnames
- mail.coreserver.jp
MX Priorities
- mail.coreserver.jp: 10
A / AAAA Records
- 104.18.24.150 (no PTR)
- 104.18.25.150 (no PTR)
Mail Server IPs
- 202.172.25.31 ↩ b30.coreserver.jp
SOA Record
Raw SOA
gabriel.ns.cloudflare.com dns.cloudflare.com 2399147664 10000 2400 604800 1800
Primary NS (mname)
gabriel.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2399147664
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
vera.ns.cloudflare.com
gabriel.ns.cloudflare.com
SPF Record
✓ Soft Fail (~all)
v=spf1 a:www.coreserver.jp ip4:202.172.25.31 include:_spf.google.com ~all
📊 DNS lookups: 2/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
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
3 records- SPFv=spf1 a:www.coreserver.jp ip4:202.172.25.31 include:_spf.google.com ~all
- SPFv=spf1 redirect=value-domain.com
- google-site-verification=M52iG-enU0nhGjZ1Rv0-Jd8Gpn3NEjwa4cWvyYct9tU
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