Cisco Secure Email (IronPort) receives mail for 67 of 9,971 popular domains we measured in November 2026. Below: the records it needs and how its customers actually set them.
MX hosts are assigned per customer, for example mx1.<customer>.iphmx.com and mx2.<customer>.iphmx.com.
Publish a TXT record at _dmarc.<domain> once SPF and DKIM pass for all mail you send, start with p=none and a reporting address, then move to p=quarantine or p=reject:
v=DMARC1; p=reject; rua=mailto:dmarc-reports@<domain>Provider site: https://www.cisco.com/site/us/en/products/security/secure-email/index.html
67 customer domains in the sample (accent bars) compared with all 9,971 measured domains (grey bars).
The highest-ranked domains in the sample whose MX records point to Cisco Secure Email (IronPort).
Check one yourself:
Customer-specific parts replaced by <domain> and digits by <n>.
| MX host pattern | Domains |
|---|---|
mx<n>.hc<n>-<n>.iphmx.com | 28 |
mx<n>.hc<n>-<n>.eu.iphmx.com | 9 |
mx<n>.hc<n>-<n>.ap.iphmx.com | 7 |
mx<n>.intuit.iphmx.com | 3 |
mx<n>.hc<n>-<n>.c<n>s<n>.iphmx.com | 2 |
mx<n>.hc<n>-<n>.ca.iphmx.com | 2 |
esa<n>.hc<n>-<n>.iphmx.com | 2 |
mx<n>.deloitte.iphmx.com | 1 |
Source: our own scan of November 2026 (2026-11-11), 9,971 of the top 10,000 domains of the Tranco list Y895G that answered in DNS. Method and data.