Email & DNS Infrastructure

Professional Email Infrastructure

Executive Summary

Designed and secured a custom email platform for jeremymcain.com using Zoho Mail and Hostinger DNS. Configured MX, SPF, DKIM, and DMARC to deliver a secure, professional communication system.

Business Problem

A recruiter- and client-facing identity needs a professional, custom-domain email address with verifiable authentication rather than a free consumer inbox — requiring DNS-level trust (MX, SPF, DKIM, DMARC) so messages are accepted and not flagged as spoofed, plus documented alias routing for distinct contact purposes.

Architecture

Zoho Mail handles inbound and outbound delivery for the domain, authenticated end-to-end through DNS records hosted at the registrar (Hostinger) rather than at Zoho.

Internet
   |
Hostinger DNS
   |
MX / SPF / DKIM / DMARC
   |
Zoho Mail
   |
jeremy@
 |-- hello@
 |-- jobs@
 |-- projects@
 |-- security@

Environment

Domain: jeremymcain.com · DNS: Hostinger · Mail: Zoho Mail

DNS Configuration

Configured Zoho Mail MX records at Hostinger to route inbound mail for the domain to Zoho.

SPF

TXT record authorizing Zoho Mail as a permitted sender for the domain (TTL 14400).

v=spf1 include:zohomail.com ~all

DKIM

Published the Zoho-generated public key as a TXT record to sign outbound mail cryptographically.

DMARC

Configured a domain policy and aggregate reporting to enforce SPF/DKIM alignment.

Email Alias Strategy

Alias	Purpose
jeremy@	Primary identity
hello@	Website
jobs@	Recruiting
projects@	Technical collaboration
security@	Security disclosures

Production Validation

DNS propagated across resolvers, MX resolution verified, SPF passed on outbound test messages, DKIM signatures validated, DMARC policy published and reporting, and delivery confirmed for every alias.

Skills Demonstrated

DNS Administration
Email Infrastructure
Zoho Mail Administration
Hostinger DNS
SPF / DKIM / DMARC
Technical Documentation

Lessons Learned

Email hosting and DNS hosting are separate services. Email aliases inherit the domain authentication configuration and do not require additional MX, SPF, DKIM, or DMARC records.