#DNS
DNS (Domain Name System) translates domain names into the records that computers need, such as IP addresses, mail servers and verification strings. Many website and e-mail problems start with a missing, duplicated or outdated DNS record. Record types such as A, CNAME, MX and TXT each have a specific role and their own rules. Changes spread according to the record’s TTL, so planning matters when moving hosts or providers. The articles under this tag explain DNS records in practical terms and show how to avoid common mistakes.
29 sept 2026 · 7 min de lecturaDKIM Key Length: 1024 vs 2048 Bits and Long DNS Records
Should your DKIM key be 1024 or 2048 bits? Learn what the standard recommends, how to publish long keys in DNS without errors and…
28 sept 2026 · 8 min de lecturaEmail Setup for a New Business Domain: Get It Right on Day One
Starting a business or a new domain? Set up MX, SPF, DKIM and DMARC, website mail and sending habits correctly from day one, before…
26 sept 2026 · 8 min de lecturaSPF Record Examples for Common Small Business Setups
Practical SPF record examples for Google Workspace, Microsoft 365, website mail, newsletter tools, own servers and parked domains, with the pitfalls to avoid.
24 sept 2026 · 8 min de lecturaIs Your Email Encrypted? TLS and STARTTLS Explained Simply
Most e-mail is encrypted between servers with TLS, but not always and not end to end. Learn how STARTTLS works, how to check it…
19 sept 2026 · 7 min de lecturaDKIM Key Rotation: When and How to Replace Your Keys Safely
DKIM keys should not live forever. Learn why to rotate them, how often, and a step-by-step process that replaces keys without breaking e-mail delivery.
16 sept 2026 · 8 min de lecturaDMARC for Subdomains: How the sp Tag Protects Your Domain
Attackers can spoof subdomains you never use. Learn how DMARC applies to subdomains, what the sp tag does, and how to set policies for…
15 sept 2026 · 8 min de lecturaChanging DNS Provider Without Breaking Your Email
Moving your domain's DNS to a new host can silently break e-mail. Learn which records to copy, how to compare zones and how to…
11 sept 2026 · 8 min de lecturaDKIM Failing? How to Troubleshoot dkim=fail and dkim=none
A step-by-step guide to fixing DKIM failures: missing keys, wrong selectors, truncated records, modified messages and signatures that use the wrong domain.
9 sept 2026 · 7 min de lecturaSPF Softfail vs Hardfail: Should You Use ~all or -all?
Should your SPF record end with ~all or -all? Learn what softfail and hardfail do, how receivers treat them with DMARC, and which ending…
29 ago 2026 · 8 min de lecturaSwitching Email Providers: A Checklist to Avoid Lost Mail
Moving business e-mail to a new provider? Follow this checklist for MX, SPF, DKIM, DMARC, TTLs and mailbox migration so no messages are lost…
21 ago 2026 · 8 min de lecturaMTA-STS and TLS-RPT: Enforcing Encrypted Email Delivery
MTA-STS makes other servers deliver your incoming mail only over verified TLS, and TLS-RPT reports failures. Learn how both work and how to set…
19 ago 2026 · 8 min de lecturaReverse DNS and PTR Records for Email: What You Need to Know
Mail servers without matching reverse DNS are treated as suspicious. Learn what PTR records are, who controls them, and how to check forward-confirmed rDNS.