Spans not exported to Zipkin with property 'spring.sleuth.sampler.probability' set to value 1

I’m developing application using Spring Boot (2.1.4) running on Kubernetes. Spans from my application aren’t exported to Zipkin while property ‘spring.sleuth.sampler.probability’ is set to value 1.

[2019-05-17T09:59:07.083Z][http-nio-8080-exec-9] TRACE; [service,71283846f6dd8fc3c096c1eae7e35142,8b3124a796b24061,false] ; org.springframework.cloud.sleuth.log.Slf4jScopeDecorator; Starting scope for span: 71283846f6dd8fc3c096c1eae7e35142/8b3124a796b24061
[2019-05-17T09:59:07.083Z][http-nio-8080-exec-9] TRACE; [service,71283846f6dd8fc3c096c1eae7e35142,8b3124a796b24061,false] ; org.springframework.cloud.sleuth.log.Slf4jScopeDecorator; With parent: -4569251557263847102
[2019-05-17T09:59:07.109Z][http-nio-8080-exec-9] TRACE; [service,71283846f6dd8fc3c096c1eae7e35142,8b3124a796b24061,false] ; org.springframework.cloud.sleuth.log.Slf4jScopeDecorator; Closing scope for span: 71283846f6dd8fc3c096c1eae7e35142/8b3124a796b24061

I set this property via Consul and verified via Actuator (endpoint actuator/configprops) that it is set properly:

                "spring.sleuth.sampler-org.springframework.cloud.sleuth.sampler.SamplerProperties": {
                    "prefix": "spring.sleuth.sampler",
                    "properties": {
                        "probability": 1
                    }
                },

Is there any additional property/header/configuration that could prevent sending spans by Sleuth to Zipkin?

[devinsba]

You need to set the sampling in istio, it is likely marking the traces as not sampled through the headers it generated

[pawcykca]

You are right! Default value of PILOT_TRACE_SAMPLING environment variable was set to 1.0 (what means 1%)

Thanks!