Chapter 10: Jenkins Introduction

10.8 Agents and Docker-in-Docker awareness

By Ravindra Bagale · Last updated: 1 October 2026

Agents need the tools your stages call (python, docker, node). Options beginners meet:

1. Bake tools into the agent image/VM.
2. Docker agent — run stages inside a container that already has the toolchain.
3. Docker commands on the agent — agent socket or DinD; DinD has security and complexity trade-offs — do not treat it casually on shared hosts.

For this intro lab, running tests with sh on a single Jenkins controller (with tools installed or via container agent) is enough. Production agent fleets are a later ops topic.