Traces are currently working properly with datadog with the exception of having the ability to facet the tags  In order to get valuable graph in dashboard the tag on the metrics need to be faceted by datadog. This PR update the tags with facetable path. While keeping backward compatibility with existing path for zipkin. Graph like:      Signed-off-by: bob <bob.bouteillier@datadoghq.com>
trace
Name
trace - enables OpenTracing-based tracing of DNS requests as they go through the plugin chain.
Description
With trace you enable OpenTracing of how a request flows through CoreDNS. Enable the debug plugin to get logs from the trace plugin.
Syntax
The simplest form is just:
trace [ENDPOINT-TYPE] [ENDPOINT]
- ENDPOINT-TYPE is the type of tracing destination. Currently only
zipkin
anddatadog
are supported. Defaults tozipkin
. - ENDPOINT is the tracing destination, and defaults to
localhost:9411
. For Zipkin, if ENDPOINT does not begin withhttp
, then it will be transformed tohttp://ENDPOINT/api/v1/spans
.
With this form, all queries will be traced.
Additional features can be enabled with this syntax:
trace [ENDPOINT-TYPE] [ENDPOINT] {
every AMOUNT
service NAME
client_server
datadog_analytics_rate RATE
}
every
AMOUNT will only trace one query of each AMOUNT queries. For example, to trace 1 in every 100 queries, use AMOUNT of 100. The default is 1.service
NAME allows you to specify the service name reported to the tracing server. Default iscoredns
.client_server
will enable theClientServerSameSpan
OpenTracing feature.datadog_analytics_rate
RATE will enable trace analytics on the traces sent from 0 to 1, 1 being every trace sent will be analyzed. This is a datadog only feature (ENDPOINT-TYPE needs to bedatadog
)
Zipkin
You can run Zipkin on a Docker host like this:
docker run -d -p 9411:9411 openzipkin/zipkin
Note the zipkin provider does not support the v1 API since coredns 1.7.1.
Examples
Use an alternative Zipkin address:
trace tracinghost:9253
or
. {
trace zipkin tracinghost:9253
}
If for some reason you are using an API reverse proxy or something and need to remap the standard Zipkin URL you can do something like:
trace http://tracinghost:9411/zipkin/api/v1/spans
Using DataDog:
trace datadog localhost:8126
Trace one query every 10000 queries, rename the service, and enable same span:
trace tracinghost:9411 {
every 10000
service dnsproxy
client_server
}
See Also
See the debug plugin for more information about debug logging.