Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
columbiabooks.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-23 13:59:59 UTC · ↺ Refresh
MX Hostnames
- columbiabooks-com.mail.protection.outlook.com
MX Priorities
- columbiabooks-com.mail.protection.outlook.com: 0
A / AAAA Records
- 107.23.119.67 ↩ ec2-107-23-119-67.compute-1.amazonaws.com
Mail Server IPs
- 52.101.11.13 ↩ mail-sn1pr0501cu00205.inbound.protection.outlook.com
- 52.101.11.10 ↩ mail-sa9pr03cu00202.inbound.protection.outlook.com
- 40.93.192.4 ↩ mail-dm2pr04cu00404.inbound.protection.outlook.com
- 52.101.41.22 ↩ mail-sj2pr05cu00406.inbound.protection.outlook.com
- 2a01:111:f403:f90d::1 ↩ mail-sn1pr0501cu00301.inbound.protection.outlook.com
- 2a01:111:f403:c902::5 ↩ mail-sj2pr05cu00505.inbound.protection.outlook.com
- 2a01:111:f403:c927::1 ↩ mail-bn8pr05cu00301.inbound.protection.outlook.com
- 2a01:111:f403:f802::1 ↩ mail-sj2pr05cu00101.inbound.protection.outlook.com
SOA Record
Raw SOA
celine.ns.cloudflare.com dns.cloudflare.com 2398752693 10000 2400 604800 1800
Primary NS (mname)
celine.ns.cloudflare.com
Admin Email (rname)
dns@cloudflare.com
Serial
2398752693
Refresh
10000s
Retry
2400s
Expire
604800s
Minimum TTL
1800s
Nameservers (NS)
celine.ns.cloudflare.com
clint.ns.cloudflare.com
SPF Record
✓ Strict (-all)
v=spf1 ip4:205.201.40.0/21 ip4:66.162.67.99 ip4:66.162.67.114 ip4:66.162.67.41 ip4:66.192.112.49 ip4:66.192.112.62 ip4:66.192.112.72 ip4:64.132.221.30 ip4:13.110.0.0/16 ip4:107.23.119.137 ip4:34.192.4.7 ip4:107.23.119.67 ip4:54.208.248.178 ip4:107.23.118.103 ip4:34.228.132.146 ip4:52.4.177.45 ip4:52.5.39.190 ip4:52.5.97.93 ip4:54.208.82.109 include:informz.net include:cust-spf.exacttarget.com include:spf.protection.outlook.com -all
📊 DNS lookups: 3/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✗ p=none
v=DMARC1; p=none; rua=mailto:[email protected]; ruf=mailto:[email protected]; fo=1
⚠ p=none — monitoring only, no enforcement
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
DKIM Selectors
✓ 2 found
selector1._domainkey
selector2._domainkey
✓ Public key: 216 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
7 records- 3e6t0qguq1887pp54thlin10jb
- MS=ms91828899
- cni2h504cr5f035qg37v86ioev
- google-site-verification=OpNIFOVGGuettmxVR86UQu7Ttc7UWzLWDo5QSSjVfM4
- google-site-verification=VweYZR2ysvGbQbCfHtZjTdH_2CvXLStK1dq4XYUAFNI
- ocdlrdp0dk77hiob26s806i6j0
- SPFv=spf1 ip4:205.201.40.0/21 ip4:66.162.67.99 ip4:66.162.67.114 ip4:66.162.67.41 ip4:66.192.112.49 ip4:66.192.112.62 ip4:66.192.112.72 ip4:64.132.221.30 ip4:13.110.0.0/16 ip4:107.23.119.137 ip4:34.192.4.7 ip4:107.23.119.67 ip4:54.208.248.178 ip4:107.23.118.103 ip4:34.228.132.146 ip4:52.4.177.45 ip4:52.5.39.190 ip4:52.5.97.93 ip4:54.208.82.109 include:informz.net include:cust-spf.exacttarget.com include:spf.protection.outlook.com -all
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