curl
Overview
curl command-line utility is capable of communicating with any REST-compatible API endpoint over HTTP(s), and OTG is no different. Although you would not want curl to be your go-to choice for OTG, mastering some key queries will be quite useful down the road.
For the examples below to work, start with initializing an environmental variable OTG_HOST with a correct URL string for your OTG API Endpoint deployment. Here we assume you've deployed the Endpoint on the same host where you'll run curl, over a default HTTPs port – similar to a basic Ixia-c Traffic Engine deployment.
To try these examples, you can download a sample otg.json configuration.
Apply a configuration
Suppose you have an OTG configuration stored in otg.json file. To apply it to an OTG Endpoint, use:
Show current configuration
Now that you have your configuration applied, you can check how the OTG Endpoint took it. You can find yourself pulling the configuration this way even when developing complex test programs or CI/CD pipelines – to see what ended up being applied to a Traffic Generator.
For example, if you want to make a small change within a complex configuration that was applied by a Test Program, show current configuration and save it to a file, make changes and apply an updated configuration from the file.
Start transmitting flows
Now that you have a configuration applied, you can start transmitting all configured Traffic Flows:
curl -sk "${OTG_HOST}/control/transmit" \
-H "Content-Type: application/json" \
-d '{"state": "start"}'
Fetch port metrics
At any moment you can a fetch current snapshot of metrics from the OTG Endpoint. Here is an example for Port Metrics. watch command is useful to pull the metrics periodically. Exit with Ctrl-C.
watch -n 1 "curl -sk \"${OTG_HOST}/results/metrics\" \
-X POST \
-H 'Content-Type: application/json' \
-d '{ \"choice\": \"port\" }'"
Fetch flow metrics
If enabled via otg.json, use this example to pull Flow Metrics. watch command is useful to pull the metrics periodically. Exit with Ctrl-C. Here, you can observe if traffic is running not only by changing counters, but also a value of transmit key: it could be started or stopped.
watch -n 1 "curl -sk \"${OTG_HOST}/results/metrics\" \
-X POST \
-H 'Content-Type: application/json' \
-d '{ \"choice\": \"flow\" }'"
Stop transmitting flows
Even more important command is to stop transmitting of all configured Traffic Flows. This is especially useful if you started a long-running test and your test program crashed after that.