TOPICS
networking
networks, DNS, mail and security
reference Cheat sheet: nftables rules for a home network The reference card taped up in my server room — commands, tables and NAT masquerade. note Postfix and SPF macros: the detail that breaks delivery A short note after one rough weekend of undelivered mail. explainer How DNS delegation works and why it matters DNS is a delegated tree: every zone can hand responsibility one level down. Understand that and you understand why changes propagate slowly and where to look for faults.