Circuit breaker working at which side?

Networking
1

Hi,
Just wondering which side circuit breaker work, it’s at service caller side or service provider side? can we specify it when creating a destinationrule resource? Thanks,

2 Likes
2

It’s enforced at the client side, i.e. sidecar on the service caller side.

3

Thanks! If there are multiple replicas calling the service, from provider perspective it should count all requests when handling but we set the circuit breaker at client side.

4

circuit breaking can be configured in both outbound(in client) and inbound(in server) in envoy proxy configuration, but in istio, we only can configure CB in outbound direction (in client) by using DestinationRule.
From istio 1.4, both inbound and outbound default CB configuration change to unlimited values.