241 lines
7.2 KiB
Plaintext
241 lines
7.2 KiB
Plaintext
---
|
|
layout: docs
|
|
page_title: Distributed Tracing
|
|
description: >-
|
|
Distributed tracing is a way to track and correlate requests across microservices.
|
|
---
|
|
|
|
# Distributed Tracing
|
|
|
|
Distributed tracing is a way to track and correlate requests across microservices. Distributed tracing must first
|
|
be implemented in each application, it cannot be added by Consul. Once implemented in your applications, adding
|
|
distributed tracing to Consul will add the sidecar proxies as spans in the request path.
|
|
|
|
## Application Changes
|
|
|
|
Consul alone cannot implement distributed tracing for your applications. Each application must propagate the required
|
|
headers. Typically this is done using a tracing library such as:
|
|
|
|
- https://github.com/opentracing/opentracing-go
|
|
- https://github.com/DataDog/dd-trace-go
|
|
- https://github.com/openzipkin/zipkin-go
|
|
|
|
## Configuration
|
|
|
|
Once your applications have been instrumented with a tracing library, you are ready to configure Consul to add sidecar
|
|
proxy spans to the trace. Your eventual config will look something like:
|
|
|
|
<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>
|
|
|
|
```hcl
|
|
Kind = "proxy-defaults"
|
|
Name = "global"
|
|
Config {
|
|
protocol = "http"
|
|
envoy_tracing_json = <<EOF
|
|
{
|
|
"http":{
|
|
"name":"envoy.tracers.zipkin",
|
|
"typedConfig":{
|
|
"@type":"type.googleapis.com/envoy.config.trace.v3.ZipkinConfig",
|
|
"collector_cluster":"collector_cluster_name",
|
|
"collector_endpoint_version":"HTTP_JSON",
|
|
"collector_endpoint":"/api/v2/spans",
|
|
"shared_span_context":false
|
|
}
|
|
}
|
|
}
|
|
EOF
|
|
|
|
envoy_extra_static_clusters_json = <<EOF
|
|
{
|
|
"connect_timeout":"3.000s",
|
|
"dns_lookup_family":"V4_ONLY",
|
|
"lb_policy":"ROUND_ROBIN",
|
|
"load_assignment":{
|
|
"cluster_name":"collector_cluster_name",
|
|
"endpoints":[
|
|
{
|
|
"lb_endpoints":[
|
|
{
|
|
"endpoint":{
|
|
"address":{
|
|
"socket_address":{
|
|
"address":"collector-url",
|
|
"port_value":9411,
|
|
"protocol":"TCP"
|
|
}
|
|
}
|
|
}
|
|
}
|
|
]
|
|
}
|
|
]
|
|
},
|
|
"name":"collector_cluster_name",
|
|
"type":"STRICT_DNS"
|
|
}
|
|
EOF
|
|
}
|
|
|
|
```
|
|
|
|
```yaml
|
|
apiVersion: consul.hashicorp.com/v1alpha1
|
|
kind: ProxyDefaults
|
|
metadata:
|
|
name: global
|
|
spec:
|
|
config:
|
|
protocol: http
|
|
envoy_tracing_json: |
|
|
{
|
|
"http":{
|
|
"name":"envoy.tracers.zipkin",
|
|
"typedConfig":{
|
|
"@type":"type.googleapis.com/envoy.config.trace.v3.ZipkinConfig",
|
|
"collector_cluster":"collector_cluster_name",
|
|
"collector_endpoint_version":"HTTP_JSON",
|
|
"collector_endpoint":"/api/v2/spans",
|
|
"shared_span_context":false
|
|
}
|
|
}
|
|
}
|
|
envoy_extra_static_clusters_json: |
|
|
{
|
|
"connect_timeout":"3.000s",
|
|
"dns_lookup_family":"V4_ONLY",
|
|
"lb_policy":"ROUND_ROBIN",
|
|
"load_assignment":{
|
|
"cluster_name":"collector_cluster_name",
|
|
"endpoints":[
|
|
{
|
|
"lb_endpoints":[
|
|
{
|
|
"endpoint":{
|
|
"address":{
|
|
"socket_address":{
|
|
"address":"collector-url",
|
|
"port_value":9411,
|
|
"protocol":"TCP"
|
|
}
|
|
}
|
|
}
|
|
}
|
|
]
|
|
}
|
|
]
|
|
},
|
|
"name":"collector_cluster_name",
|
|
"type":"STRICT_DNS"
|
|
}
|
|
```
|
|
|
|
```json
|
|
{
|
|
"Kind": "ProxyDefaults",
|
|
"Name": "global",
|
|
"Config": {
|
|
"protocol": "http",
|
|
"envoy_tracing_json": "{\"http\":{\"name\":\"envoy.tracers.zipkin\",\"typedConfig\":{\"@type\":\"type.googleapis.com/envoy.config.trace.v3.ZipkinConfig\",\"collector_cluster\":\"collector_cluster_name\",\"collector_endpoint_version\":\"HTTP_JSON\",\"collector_endpoint\":\"/api/v2/spans\",\"shared_span_context\":false}}}",
|
|
"envoy_extra_static_clusters_json": "{\"connect_timeout\":\"3.000s\",\"dns_lookup_family\":\"V4_ONLY\",\"lb_policy\":\"ROUND_ROBIN\",\"load_assignment\":{\"cluster_name\":\"collector_cluster_name\",\"endpoints\":[{\"lb_endpoints\":[{\"endpoint\":{\"address\":{\"socket_address\":{\"address\":\"collector-url\",\"port_value\":9411,\"protocol\":\"TCP\"}}}}]}]},\"name\":\"collector_cluster_name\",\"type\":\"STRICT_DNS\"}"
|
|
}
|
|
}
|
|
```
|
|
|
|
</CodeTabs>
|
|
|
|
-> **NOTE:** This example uses a [proxy defaults](/docs/connect/config-entries/proxy-defaults) config entry which will apply to all proxies
|
|
but you can also apply this config in the
|
|
[proxy service registration](/docs/connect/registration/service-registration#proxy-parameters) (not supported on Kubernetes).
|
|
|
|
Within the config there are two keys you need to customize:
|
|
|
|
1. [`envoy_tracing_json`](/docs/connect/proxies/envoy#envoy_tracing_json): Sets the tracing configuration for your specific tracing type.
|
|
See the [Envoy tracers documentation](https://www.envoyproxy.io/docs/envoy/latest/api-v3/config/trace/trace) for your
|
|
specific collector's configuration. This configuration will reference the cluster name defined in `envoy_extra_static_clusters_json`.
|
|
1. [`envoy_extra_static_clusters_json`](/docs/connect/proxies/envoy#envoy_extra_static_clusters_json): Defines the address
|
|
of your tracing collector where Envoy will send its spans. In this example the URL was `collector-url:9411`.
|
|
|
|
## Applying the configuration
|
|
|
|
This configuration only applies when proxies are _restarted_ since it changes the _bootstrap_ config for Envoy
|
|
which can only be applied on startup. This means you must restart all your proxies for changes to this
|
|
config to take effect.
|
|
|
|
-> **Note:** On Kubernetes this is a matter of restarting your deployments, e.g. `kubectl rollout restart deploy/deploy-name`.
|
|
|
|
## Considerations
|
|
|
|
1. Distributed tracing is only supported for HTTP and gRPC services. You must specify the protocol either globally
|
|
via a proxy defaults config entry:
|
|
|
|
<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>
|
|
|
|
```hcl
|
|
Kind = "proxy-defaults"
|
|
Name = "global"
|
|
Config {
|
|
protocol = "http"
|
|
}
|
|
```
|
|
|
|
```yaml
|
|
apiVersion: consul.hashicorp.com/v1alpha1
|
|
kind: ProxyDefaults
|
|
metadata:
|
|
name: global
|
|
spec:
|
|
config:
|
|
protocol: http
|
|
```
|
|
|
|
```json
|
|
{
|
|
"Kind": "proxy-defaults",
|
|
"Name": "global",
|
|
"Config": {
|
|
"protocol": "http"
|
|
}
|
|
}
|
|
```
|
|
|
|
</CodeTabs>
|
|
|
|
Or via a service defaults config entry for each service:
|
|
|
|
<CodeTabs tabs={[ "HCL", "Kubernetes YAML", "JSON" ]}>
|
|
|
|
```hcl
|
|
Kind = "service-defaults"
|
|
Name = "service-name"
|
|
Protocol = "http"
|
|
```
|
|
|
|
```yaml
|
|
apiVersion: consul.hashicorp.com/v1alpha1
|
|
kind: ProxyDefaults
|
|
metadata:
|
|
name: service-name
|
|
spec:
|
|
protocol: http
|
|
```
|
|
|
|
```json
|
|
{
|
|
"Kind": "service-defaults",
|
|
"Name": "service-name",
|
|
"Protocol": "http"
|
|
}
|
|
```
|
|
|
|
</CodeTabs>
|
|
|
|
1. Requests through [Ingress Gateways](/docs/connect/gateways/ingress-gateway) will not be traced unless the header
|
|
`x-client-trace-id: 1` is set (see [hashicorp/consul#6645](https://github.com/hashicorp/consul/issues/6645)).
|
|
|
|
1. Consul does not currently support interoperation with [OpenTelemetry](https://opentelemetry.io/) libraries due to
|
|
Envoy not yet having support.
|
|
|
|
1. Tracing is only supported with Envoy proxies, not the built-in proxy.
|