Cernan is an open source telemetry and logging aggregation server. From the Cernan wiki:
Cernan exposes multiple interfaces for ingestion and can emit to multiple aggregation sources while doing in-flight manipulation of data. Cernan has minimal CPU and memory requirements and is intended to service bursty telemetry without load shedding. Cernan aims to be reliable and convenient to use, both for application engineers and operations staff.
Cernan is packaged with a built-in sink for Wavefront. This makes it very convenient to get Cernan connected to Wavefront.
Step 1. Set up Wavefront Proxy
If you do not have a Wavefront proxy installed on your network, install a proxy.
Step 2. Follow the Cernan Quickstart
Follow the Cernan Quickstart.
In particular, make sure you are sending a test metric
foo.bar to Cernan. The command
while true; do echo "foo.bar:225|g" | nc -c -u localhost 8125; done will send a constant of
225 as the
After following these steps you should have Cernan running and are seeing sample output printed to your terminal that looks similar to below:
Flushing metrics: 2017-01-30T17:49:29.782336+00:00 sums: sets: foo.bar(1485798558): 225 summaries: Flushing metrics: 2017-01-30T17:49:39.562324+00:00 sums: sets: foo.bar(1485798569): 225 summaries: Flushing metrics: 2017-01-30T17:49:49.856861+00:00 sums: sets: foo.bar(1485798579): 225 summaries:
This output is being printed by the console source which is configured in the example
Step 3. Configure the Wavefront Sink
From your Cernan root directory, copy the
quickstart.tomlfile into a new file called
$ cp examples/configs/quickstart.toml examples/configs/quickstart-wavefront.toml
At this point, the entire
quickstart-wavefront.tomlshould look like:
flush-interval = 10 [sources] [sources.statsd.primary] port = 8125 forwards = ["sinks.console","sinks.wavefront"] [sinks] [sinks.console] [sinks.wavefront] bin_width = 10 host = "WAVEFRONT_PROXY_ADDRESS" port = 2878
Update the host and port to reflect your Wavefront proxy address.
Run Cernan with the new config file:
$ cargo run -- -vv --config examples/configs/quickstart-wavefront.toml
You should see the same output in your Cernan terminal as you did previously, but now the metrics should be sending to Wavefront in addition to being printed to the console.
Log into Wavefront and open a new chart. Enter a query for the new metric “foo.bar”:
It may take up to a minute for a brand new metric to appear in Wavefront. If you’re not seeing the foo.bar metric after a couple of minutes, check the following:
- The console output from Cernan - it will display an error if it cannot connect to the Wavefront proxy.
- The Wavefront proxy logs - if Cernan is sending any bad lines to the Wavefront proxy, the proxy will block the lines and display error messages in the logs.