Merge branch 'v1.7' into master

docs/configuration/tracing.md

@@ -4,7 +4,7 @@ Tracing system allows developers to visualize call flows in there infrastructure
 
 We use [OpenTracing](http://opentracing.io). It is an open standard designed for distributed tracing.
 
-Træfik supports two backends: Jaeger and Zipkin.
+Træfik supports three tracing backends: Jaeger, Zipkin and DataDog.
 
 ## Jaeger
 
@@ -22,6 +22,13 @@ Træfik supports two backends: Jaeger and Zipkin.
   # Default: "traefik"
   #
   serviceName = "traefik"
+    
+  # Span name limit allows for name truncation in case of very long Frontend/Backend names
+  # This can prevent certain tracing providers to drop traces that exceed their length limits
+  #
+  # Default: 0 - no truncation will occur
+  # 
+  spanNameLimit = 0
 
   [tracing.jaeger]
     # Sampling Server URL is the address of jaeger-agent's HTTP sampling server
@@ -84,6 +91,13 @@ Træfik supports two backends: Jaeger and Zipkin.
   # Default: "traefik"
   #
   serviceName = "traefik"
+    
+  # Span name limit allows for name truncation in case of very long Frontend/Backend names
+  # This can prevent certain tracing providers to drop traces that exceed their length limits
+  #
+  # Default: 0 - no truncation will occur
+  # 
+  spanNameLimit = 150
 
   [tracing.zipkin]
     # Zipking HTTP endpoint used to send data
@@ -127,6 +141,13 @@ Træfik supports two backends: Jaeger and Zipkin.
   # Default: "traefik"
   #
   serviceName = "traefik"
+  
+  # Span name limit allows for name truncation in case of very long Frontend/Backend names
+  # This can prevent certain tracing providers to drop traces that exceed their length limits
+  #
+  # Default: 0 - no truncation will occur
+  # 
+  spanNameLimit = 100
 
   [tracing.datadog]
     # Local Agent Host Port instructs reporter to send spans to datadog-tracing-agent at this address