Shadow Traffic¶
This tutorial will show how to setup routing for shadow traffic, where one backend (main) will receive the full traffic, while a shadowing backend (test) will receive only a certain percentage of the same traffic.
Used Predicates:¶
Used Filters:¶
1. Initial state¶
Before the shadow traffic, we are sending all traffic to the main backend.
main: * -> "https://main.example.org";
2. Clone the main route, handling 10% of the traffic¶
Before generating the shadow traffic, we create an identical clone of the main route that will handle only 10% of the traffic, while the rest stays being handled by the main route.
main: * -> "https://main.example.org";
split: Traffic(.1) -> "https://main.example.org";
3. Prepare the route for the shadow traffic¶
The route introduced next won’t handle directly any incoming requests, because they won’t be matched by the Tee predicate, but it is prepared to send tee requests to the alternative, ‘shadow’ backend.
main: * -> "https://main.example.org";
split: Traffic(.1) -> "https://main.example.org";
shadow: Tee("shadow-test-1") && True() -> "https://shadow.example.org";
4. Apply the teeLoopback filter¶
Now we can apply the teeLoopback filter to the ‘split’ route, using the same label as we did in the Tee predicate.
main: * -> "https://main.example.org";
split: Traffic(.1) -> teeLoopback("shadow-test-1") -> "https://main.example.org";
shadow: Tee("shadow-test-1") && True() -> "https://shadow.example.org";
Note that as of now, we need to increase the weight of the ‘shadow’ route by adding the True() predicate in order to avoid that the ‘split’
route would match the cloned request again.
After this, the ‘split’ route will still send all the handled requests, 10% of the total traffic, to the main backend, while the rest of the traffic is routed there by the ‘main’ route. However, the teeLoopback filter will also clone the traffic of the ‘split’ route, 10% of the total, and reapply the routing on it, during which these requests will be matched by the Tee predicate, and sent to the shadow backend.