Snappi Open Traffic Generator

1.53.0 verified Mon Apr 27 auth: no python

Snappi is an open-source Python library for generating and testing network traffic. The current version is 1.53.0, with regular releases approximately every 2-3 weeks. It supports Python >=3.8,<4 and integrates with various traffic generator backends (e.g., IxNetwork, Traffic Server). Snappi provides a unified API to configure traffic flows, endpoints, and capture settings.

pip install snappi

Common errors

error ModuleNotFoundError: No module named 'snappi' ↓

cause snappi not installed or running in a different Python environment.

fix

Run 'pip install snappi' in the correct environment.

error AttributeError: module 'snappi' has no attribute 'Api' ↓

cause Import was not done correctly (e.g., from snappi import snappi).

fix

Use 'import snappi' then 'snappi.Api(...)'.

error ConnectionError: HTTPConnectionPool ... Max retries exceeded ↓

cause The controller address is incorrect or the server is not running.

fix

Verify the API address (e.g., 'https://localhost:11009') and ensure the snappi server is running.

error ValueError: Unsupported protocol version ↓

cause Client version incompatible with server version (server may be older).

fix

Upgrade both client and server to the latest version, or pin to compatible versions.

error TypeError: 'NoneType' object is not iterable ↓

cause Attempting to iterate over a flow before it is properly configured or added.

fix

Ensure you have added flows to config, e.g., config.flows.flow(name='test')...

Warnings

gotcha The API address must include the protocol (http/https) and port. Local default is https://localhost:11009. ↓

fix Always specify full URL: api = snappi.Api(address='https://10.10.10.10:8443')

deprecated Method set_config() and resulting 'elapsed_time' attribute are deprecated in v1.50+. Use set_config() -> config object directly. ↓

fix Use config = api.config() then api.set_config(config)

breaking In v1.40.0, the default protocol changed from HTTP to HTTPS. Older code using http:// may fail. ↓

fix Update API address to https:// or set ssl=False explicitly.

gotcha Flow packet layers are built using chained methods (e.g., .packet().ethernet().eth_ipv4()). Order matters; .eth_ipv4() is a shorthand for stacking ethernet and IPv4. ↓

fix Use .packet().ethernet().ipv4() for separate layers or .eth_ipv4() for convenience.

breaking The 'config.ports' property was renamed to 'config.port' in v1.20.0. ↓

fix Use config.port instead of config.ports.

gotcha When setting packet headers, some fields require .value assignment, others use .increment or .decrement. Not all fields support all modes. ↓

fix Check docstring: e.g., ipv4.src.increment.start = '10.0.0.1'; ipv4.src.value = '10.0.0.1'

Imports

Api
wrong
```
from snappi import snappi
```
correct
```
import snappi
```
The library is a package; the main API class is accessed via snappi.Api(), not a submodule.

Quickstart

Instantiate the API, create a config, and add a simple IPv4 flow.

import snappi

api = snappi.Api(address='https://localhost:11009')
config = api.config()
config.flows.flow(name='test_flow').packet().ethernet().eth_ipv4().v4().src.value = '10.0.0.1'
# No auth needed for local; for remote, set via os.environ.get('SNAPPI_AUTH_TOKEN', '')