Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
costcotravel.com
Yes
✓ Yes
Outlook
No
No
⚠ Yes
No
No
Checked via [email protected]
· 2026-03-18 03:03:16 UTC · ↺ Refresh
MX Hostnames
- costcotravel-com.mail.protection.outlook.com
MX Priorities
- costcotravel-com.mail.protection.outlook.com: 10
A / AAAA Records
- 23.208.47.52 ↩ a23-208-47-52.deploy.static.akamaitechnologies.com
Mail Server IPs
- 52.101.41.4 ↩ mail-sj2pr05cu00204.inbound.protection.outlook.com
- 52.101.41.58 ↩ mail-sj0pr02cu00102.inbound.protection.outlook.com
- 52.101.194.15 ↩ mail-ch4pr21cu00107.inbound.protection.outlook.com
- 52.101.194.13 ↩ mail-ch0pr04cu00605.inbound.protection.outlook.com
SOA Record
Raw SOA
a1-158.akam.net hostmaster.akamai.com 1555373172 3600 1800 1209600 300
Primary NS (mname)
a1-158.akam.net
Admin Email (rname)
hostmaster@akamai.com
Serial
1555373172
Refresh
3600s
Retry
1800s
Expire
1209600s
Minimum TTL
300s
Nameservers (NS)
a2-65.akam.net
a13-64.akam.net
a6-67.akam.net
a28-66.akam.net
a1-158.akam.net
a11-67.akam.net
SPF Record
✓ Strict (-all)
v=spf1 ip4:208.185.193.64/26 ip4:170.167.255.0/24 include:spf.protection.outlook.com -all
📊 DNS lookups: 1/10
✓ Hard fail (-all) — strict enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; pct=100; rua=mailto:[email protected],mailto:[email protected],mailto:[email protected]; ruf=mailto:[email protected],mailto:[email protected]; fo=1
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected],mailto:[email protected],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
11 records- dtm-domain-verification=XPvKk0MfjwWjb87NE0pYnt9VQ_FsqB5Xt4JC9o1T6TA
- docusign=e8e75115-a119-46b1-96f0-6822528a23b5
- mongodb-site-verification=YcHwWNcnbTdu9fFB5tDEzYG7EuvxM5Pm
- adobe-idp-site-verification=00ed8cd2a8c54d2776489c27085f5136e1e4de577e5fec6e54ed62c28e548813
- facebook-domain-verification=xgvxxjhne280ibrpuuixsap38o6aem
- atlassian-domain-verification=FsOsp1KAAEckd2nGgLjDu5RxMta8DpJUy2kQUXWOBQzjO8Fta7LqmgdwoPZ+j6uh
- vdH7pFKR2Cy1u8EIefPIjKibEN0IaGWmm1d07lMRlCuUUEui9ry/88RggCqLWtjgvHWql1CP+5noWR2WfKDCKA==
- docusign=3d6127d3-7582-4c25-acd4-9970951f0a74
- MS=ms98332774
- SPFv=spf1 ip4:208.185.193.64/26 ip4:170.167.255.0/24 include:spf.protection.outlook.com -all
- MS=B52D493A0A7187C5E881285CFAE8017560F7CE6B
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