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Practical field notes for teams diagnosing email deliverability, DNS authentication, sender reputation, Linux, MTA, cloud, monitoring, and DevOps failures.

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Technical knowledge system connecting email identity, secure mail flow, servers, cloud operations, monitoring, and runbooks

182 Published articles

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Technical notes

Articles on email deliverability, DNS, Linux, MTA operations, DevOps, monitoring, and incident recovery.

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Short, practical guidance for teams that need to diagnose, repair, and run production email systems.

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Acquisition sources pass consent, syntax, confirmation and engagement controls before clean audiences or suppression, with pristine, seeded, typo and recycled trap-risk categories

Email Deliverability · Feb 19, 2026 · 13 min read

Email Spam Traps: Types, Diagnosis and Prevention

A source-focused guide to spam-trap risk that avoids trap hunting and repairs the acquisition, permission or inactivity process that allowed risky addresses.

Shared and dedicated email IP models are compared by volume, isolation, operational staffing, ramp capacity and cost before common authentication and monitoring controls

Email Infrastructure & Authentication · Feb 18, 2026 · 12 min read

Dedicated vs Shared IP for Email: Capacity and Reputation

A practical infrastructure decision framework that compares shared pools and dedicated IPs without treating either model as an automatic deliverability upgrade.

Authorized sending IPs feed Microsoft SNDS telemetry into daily baselines, anomaly detection, SMTP and JMRP correlation, scoped containment and recovery verification

Email Deliverability · Feb 17, 2026 · 13 min read

Microsoft SNDS: Monitor Outlook IP Reputation and Traffic

A practical operations guide to Microsoft Smart Network Data Services, including access authorization, baselines, incident correlation and the limits of SNDS data.

An email blocklist incident moves from monitoring and exact listing confirmation through SMTP evidence, containment, root-cause analysis, remediation, delisting and verification

Email Deliverability · Feb 16, 2026 · 12 min read

Email Blocklists: Monitoring, Diagnosis and Delisting

An incident-response method for IP, domain and URL blocklist listings, from evidence and containment through remediation, delisting and recovery monitoring.

A sending MTA discovers an MTA-STS DNS record, retrieves and caches an HTTPS policy, validates MX STARTTLS certificates and either delivers or queues for retry

Email Infrastructure & Authentication · Feb 15, 2026 · 13 min read

MTA-STS: Enforce TLS for Inbound Email Delivery

A staged implementation guide for MTA-STS policy hosting, MX matching, certificate validation, testing, enforcement, monitoring and incident recovery.

A recipient domain publishes a TLS-RPT DNS policy while sending MTAs aggregate TLS successes and failures into JSON reports, parsing, alerts and remediation

Email Infrastructure & Authentication · Feb 14, 2026 · 13 min read

TLS-RPT for Email: Publish, Read and Act on Reports

An operations guide to publishing TLS-RPT, ingesting aggregate JSON safely and converting transport-security reports into actionable evidence.

An email and paid-channel customer journey is evaluated through first-touch, last-touch, multi-touch and incrementality lenses before revenue, cost, margin and confidence

Analytics & Optimization · Feb 13, 2026 · 13 min read

Email Attribution Models: Measuring Incremental Revenue

A measurement guide that separates attribution credit from causal lift and connects email touchpoints to revenue, margin, cohorts and holdout evidence.

An originating message is assessed with SPF, DKIM and DMARC before a forwarder adds ARC authentication results, a message signature and a seal for final receiver validation

Email Infrastructure & Authentication · Feb 12, 2026 · 14 min read

Authenticated Received Chain (ARC): Forwarding and Mailing Lists

How ARC preserves authenticated handling evidence across forwarders and mailing lists, what receivers can infer from it and how to troubleshoot a broken chain.

One source email enters a rendering test matrix for desktop, mobile, webmail and dark mode before layout, font, image, link, accessibility and fallback checks reach a QA gate

Content, Design & Testing · Feb 11, 2026 · 14 min read

Email Rendering Testing Across Clients and Devices

A release-oriented approach to testing HTML email across real client families, screen sizes, accessibility settings, dark mode and failure fallbacks.