Do Network Engineers Need to Code? Python and Network Automation

A network engineer can get hired without writing code, and many entry-level roles still ask only for routing, switching, and troubleshooting skills. Automation, however, is now part of most senior network roles, and Python is the language that covers nearly all of it. The practical answer is therefore: you do not need to code to start, but you will need Python to advance.

Network automation means using programs to configure, check, and repair network devices instead of typing commands into each one by hand. A team that runs 400 switches cannot log in to each switch to change one line, so the change is written once as a script and pushed everywhere. That change in scale is the reason coding now appears in network job descriptions.

Which network tasks need code

Four kinds of task need code, and each has a standard tool.

Pushing configuration to many devices. A script logs in over SSH, sends the configuration lines, and records the result for every device. Python with Netmiko handles this, and Netmiko is a library that wraps SSH sessions to routers and switches from Cisco, Juniper, Arista, and others.

Collecting telemetry. Telemetry is the stream of counters and state that a device reports, such as interface errors or BGP neighbor status. NAPALM is a Python library that reads this state in the same format across vendors, so one script works on a mixed network.

Validating state after a change. A change is not finished until the network is confirmed to be in the expected state. Nornir is a Python framework that runs these checks across hundreds of devices at the same time and reports which ones failed.

Building self-service tooling. Application teams want to request a firewall rule or a VLAN without filing a ticket. Modern network operating systems expose REST APIs, which are HTTP endpoints that accept JSON, so a small web tool can make the change directly.

Ansible is a fourth option. It describes changes in YAML playbooks, which are plain text files listing the desired state, so a team can automate without writing Python at all. Go is used for high-performance tooling such as telemetry collectors that process millions of records per minute, but it is a specialist choice rather than a starting point.

How much coding appears in network interviews

A network-engineer interview rarely contains an algorithm question of the kind software engineers face. Nobody will ask you to invert a binary tree. What does appear, in most senior interviews, is a scripting question that checks whether you can automate a routine task.

Two examples are typical. The first: "Here is a router configuration as a text file. Write a script that lists every interface with no description". A good answer reads the file line by line, matches interface lines, and prints the ones not followed by a description line. The second: "Given this REST API for our controller, write a call that returns every device with a down uplink". A good answer sends a GET request with the requests library, parses the JSON, and filters on the status field.

Both tasks take 10 to 15 lines of Python. The interviewer is checking that you can read text, call an API, and handle a missing field without the script crashing.