Tools // Automation

Config Template Generator

Template + JSON parameters//One config per device

How to use

Paste your device Parameters as JSON and a Template on the right, then hit Generate. A JSON array renders one config per element (named <hostname>.cfg); a single object renders one config.

{{ hostname }} — insert a variable
{{ vlan.id }} — nested field (dotted path)
{% for vlan in vlans %} … {% endfor %} — loop over a list
{% if up %} … {% elif x %} … {% else %} … {% endif %} — conditionals
Filters: {{ name | upper }}, {{ desc | default('n/a') }}, {{ vlans | length }}, {{ tags | join(', ') }}
Inside loops: loop.index, loop.index0, loop.first, loop.last

Whitespace follows default Jinja2 (block tags keep surrounding blank lines). Undefined variables render as empty.

Load example

Parameters (JSON)

Template

Templating device configs

Network configs are 95% identical text with a handful of values that change per device — hostname, management IP, VLAN list. A template captures the fixed part once and leaves placeholders for the rest, so you render one correct, consistent config per device instead of copy-pasting and hand-editing (the source of most change-window outages).

config = template (fixed structure) + parameters (per-device values)

How it works

Write a Jinja2-style template with {{ variables }} and feed it a JSON object of parameters; the tool substitutes the values and returns the finished config. Supply a JSON array and you get one config per element — a whole fleet in a single pass. It is the same idea Ansible and Terraform use, distilled to a copy-paste-friendly form for quick, one-off jobs.

template:  hostname {{ name }}
           interface mgmt0
            ip address {{ mgmt_ip }} 255.255.255.0
params:    { "name": "sw01", "mgmt_ip": "10.0.0.11" }
result:    hostname sw01
           interface mgmt0
            ip address 10.0.0.11 255.255.255.0

YAML Validator · JSON Syntax Tester
Insomnia as an API remote control — push the rendered config over an API.

Templating device configs

How it works

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