DNS (en Inglés) - Tom Martinson

This book fixes that. By the end you will have two DNS servers that answer for your internal names, stay synchronized without your attention, keep working when your internet connection does not, and can be handed to another administrator with documentation they can follow.

Written for the accidental sysadmin - the person at a company of 1 to 250 people who was handed the network and told to make it work. Every command was run end to end on live servers: a primary, a secondary, a client, and a hidden primary that was destroyed on purpose to test the recovery runbook. Where a command behaves in a way that would surprise you, the book says so.

Part One builds and operates a primary/secondary pair with BIND 9 on Ubuntu Server: naming, addressing, the theory you need to decide safely, an eleven-step build, testing, troubleshooting, recovery when the primary dies, and rotating the transfer key. It is a complete DNS service on its own.

Part Two is optional and independent: a hidden primary that turns a dead server into a task for Monday, health-aware round robin with a small Python controller, and DNS filtering with response policy zones.

No subscriptions. No appliances. Two small servers, text files you can read, and the skill to run them.