Domain Overview
DNS: ✓ 2mo ago
Checker: ✓ 2mo ago
duo.com
Yes
✓ Yes
Unknown
No
No
⚠ Yes
No
No
Did you mean: [email protected]
Checked via [email protected]
· 2026-03-26 05:32:46 UTC · ↺ Refresh
MX Hostnames
- rcdn-mx-01.cisco.com
- alln-mx-01.cisco.com
- aer-mx-01.cisco.com
MX Priorities
- rcdn-mx-01.cisco.com: 20
- aer-mx-01.cisco.com: 30
- alln-mx-01.cisco.com: 10
A / AAAA Records
- 18.238.55.44 ↩ server-18-238-55-44.jfk52.r.cloudfront.net
- 18.238.55.72 ↩ server-18-238-55-72.jfk52.r.cloudfront.net
- 18.238.55.21 ↩ server-18-238-55-21.jfk52.r.cloudfront.net
- 18.238.55.16 ↩ server-18-238-55-16.jfk52.r.cloudfront.net
Mail Server IPs
- 72.163.7.166 ↩ rcdn-mx-01.cisco.com
- 2001:420:1101:7::48a3:166 ↩ rcdn-mx-01.cisco.com
- 173.38.212.150 ↩ aer-mx-01.cisco.com
- 2001:420:4621::ad26:d496 ↩ aer-mx-01.cisco.com
- 173.37.147.230 ↩ alln-mx-01.cisco.com
- 2001:420:1201:6::ad25:93e6 ↩ alln-mx-01.cisco.com
SOA Record
Raw SOA
ns-55.awsdns-06.com awsdns-hostmaster.amazon.com 1 7200 900 1209600 86400
Primary NS (mname)
ns-55.awsdns-06.com
Admin Email (rname)
awsdns-hostmaster@amazon.com
Serial
1
Refresh
7200s
Retry
900s
Expire
1209600s
Minimum TTL
86400s
Nameservers (NS)
ns-55.awsdns-06.com
ns-932.awsdns-52.net
ns-1365.awsdns-42.org
ns-1733.awsdns-24.co.uk
SPF Record
✓ Soft Fail (~all)
v=spf1 ip4:72.35.40.113/28 ip4:66.51.154.240/29 include:_spf.google.com include:_spf.salesforce.com include:mktomail.com include:stspg-customer.com include:_spf.intacct.com include:servers.mcsv.net ~all
📊 DNS lookups: 6/10
~ Soft fail (~all) — moderate enforcement
DMARC Record
✓ Reject
v=DMARC1; p=reject; sp=reject; adkim=r; aspf=r; fo=1; rf=afrf; pct=100; ri=86400; ruf=mailto:[email protected]; rua=mailto:[email protected]
✓ Reject — strongest protection
📋 SPF alignment: Relaxed
· DKIM alignment: Relaxed
📧 Reports → mailto:[email protected]
↳ Subdomain policy: reject
DKIM Selectors
✓ 4 found
google._domainkey
k1._domainkey
s1._domainkey
s2._domainkey
✓ Public key: 216 chars (valid)
✓ DKIM properly configured for selector: google
Checked: google, selector1/2, default, mail, dkim, k1, s1/2, zoho, sendgrid, mxvault, amazonses
All TXT Records
15 records- SPFv=spf1 ip4:72.35.40.113/28 ip4:66.51.154.240/29 include:_spf.google.com include:_spf.salesforce.com include:mktomail.com include:stspg-customer.com include:_spf.intacct.com include:servers.mcsv.net ~all
- google-site-verification=uo-yyMBObeQzZDH55aAFLRLyf0IiN20p0GJ0H6N2jQQ
- google-site-verification=WvGzO9Z62GF-06EZawhrguz4lX-3soAJz8l5Zdd0kpc
- google-site-verification=FyHTkA00weOnJqC50U6D_1Etz0FeTAV36UzX-mR0t7Y
- apple-domain-verification=0NFHW4xLPA7qMAUl
- google-site-verification=zagew00MIXPj4NT7NSuvolRYA9BWUFvOvUU9On5SkLs
- workplace-domain-verification=M0nohbh4MpXazNtpfeLQrdlEAbaeQ3
- google-site-verification=UxTqzaF64RMmCuE_cfz67aerfbJyPW7jSWJaDRf8U4Q
- identrust_validate=VOOjXXB2PpF7kC14MiiEHi40phwnkIP1dhJ1AbyZxWKP
- google-site-verification=QSlNcf5REPqDzZZtYQdQ02iTtFdCkF4iGzRgOHWeAfk
- google-site-verification=F16Zf7RnF8CVcYnsbn6C308KFSeldSRrLiJK1cCgoBQ
- google-site-verification=gY1gXbTT44Hc2xjnx-TmKdBLXKzpthxWKGhlqJL0EDw
- google-site-verification=88KLpNEv0nOJ-yRHH3mp3TIvrG4rhNTP3DbODLQeIYg
- google-site-verification=_6xJQkVWQvhjZ8WH17r2qEjOu0CYifwUq5DqV-aUPIE
- identrust_validate=SMpkw2Y899uXgKrzdHnqptIfXiIOyDNlX1foFF1S209M
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