Python for Network Engineers
A twelve-part series for network engineers who want to automate their work with Python. No prior programming knowledge assumed. Starts from environment setup and works up through SSH automation, structured data, config generation, REST APIs, vendor-agnostic frameworks, parallel execution, and finally AI-augmented automation — all grounded in real Containerlab labs and multi-vendor examples.
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Python for Network Engineers — Part 1: Why Python in 2026, Environment Setup, and Your AI Pair Programmer
The first post in a 12-part series covering Python for network engineers from first principles to production automation. We cover why Python is still the right choice in 2026, how to set up a modern development environment, and how to use AI tools as a genuine pair programmer throughout your learning journey.
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Python for Network Engineers — Part 2: Strings, Numbers, Files, Lists, and Tuples
Part 2 of the Python for Network Engineers series. We cover Python's core data types — strings, numbers, booleans, files, lists, and tuples — with every example drawn from real network engineering scenarios.
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Python for Network Engineers — Part 3: Dictionaries, Sets, Comprehensions, and Exceptions
Part 3 of the Python for Network Engineers series. Dictionaries model device state. Sets expose VLAN drift between switches in one line. Comprehensions replace verbose loops. Exception handling keeps automation running when devices misbehave.
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Python for Network Engineers — Part 4: Functions, Regular Expressions, and Modules
Part 4 of the Python for Network Engineers series. Functions make your automation reusable and testable. Regular expressions parse the CLI output that structured tools can't reach. Modules turn a script into a project.
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Python for Network Engineers — Part 5: Netmiko — SSH Automation Across Vendors
Part 5 of the Python for Network Engineers series. We connect to real network devices over SSH using Netmiko, run show commands, push configuration, and build a multi-device inventory collector — with a Containerlab lab you can run at home.
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Python for Network Engineers — Part 6: Parsing CLI Output — From Regex to AI
Part 6 of the Python for Network Engineers series. Raw CLI output is a string — not data. We cover TextFSM templates, the NTC-templates library, Genie parsers, and AI-assisted parsing for commands where no community template exists.
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Python for Network Engineers — Part 7: YAML, JSON, and Validating Your Inventory with Pydantic
Part 7 of the Python for Network Engineers series. YAML for human-maintained inventory and config files. JSON for API responses and storing collected data. Pydantic to validate that what you read actually matches what you expect before it reaches your automation logic.
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Python for Network Engineers — Part 8: Jinja2 — Generating Configs at Scale
Part 8 of the Python for Network Engineers series. Jinja2 turns structured data into device configuration. Variables, loops, conditionals, filters, macros, and template inheritance — with Arista, Cisco, and Fortinet examples throughout.
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Python for Network Engineers — Part 9: REST APIs — The Modern Control Plane
Part 9 of the Python for Network Engineers series. Every modern network platform exposes a REST API. We cover the requests library, authentication patterns, pagination, error handling, and two real-world examples: Arista eAPI against our existing lab, and the FortiManager JSON-RPC API.
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Python for Network Engineers — Part 10: NAPALM — Vendor-Agnostic Network Automation
Part 10 of the Python for Network Engineers series. NAPALM provides a vendor-agnostic Python interface to network devices — the same code collects state or replaces configuration on Arista, Cisco, Juniper, or Fortinet without modification. We cover getters, config replace, dry-run validation, and the config diff workflow.
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Python for Network Engineers — Part 11: Nornir — Parallel Automation at Scale
Part 11 of the Python for Network Engineers series. Nornir is a pure-Python automation framework that runs tasks across an inventory in parallel. We cover YAML inventory, task functions, result handling, host/group filtering, and the Netmiko and NAPALM plugins — bringing together everything from the series into one coherent framework.
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Python for Network Engineers — Part 12: AI-Assisted Network Automation
The final post in the Python for Network Engineers series. We look at how to put AI tools to work inside the automation workflows we've built — config review, fleet-wide AI-assisted parsing, a minimal MCP server that lets an AI agent call your automation scripts, and the discipline that keeps AI-assisted automation safe.