Collectors ship data over HTTPS to AOC every 1 second or more for protocol metrics and every 10 seconds for infrastructure metrics. The AOC returns response to the collectors, indicating if the data was correctly received or if there was an error. The data is formatted as a protobuf binary and compressed JSON. In addition to metrics the collectors also report health data for various collector components to AOC and in turn recieve configuration data and information about available upgrades.
Netsil collectors collect the following aggregate metric data:
From the network packets Database activity on the network Transactions in HTTP, Thrift RPC, HTTP/2, GRPC and other supported protocols * DNS activity This aggregate metric data summarizes calls within each protocol in your application: how many times each one was called and various response time statistics (average, minimum, maximum, and standard deviation). In AOC user interface, you will see L7 routes and method names with their aggregate numbers.
From the infrastructure Process memory and CPU usage Metrics collected from configured integrations * Metrics and Events sent to the Statsd server
Network data collection¶
Netsil uses libpcap to passively observe the traffic. The packets are processed in a streaming fashion. Useful metadata fields are captured from the packets and the rest is discarded. Ip addresses and server port is captured from L3-L4 and for supported L7 protocols certain metadata fields are captured from the L7 headers and payload. For e.g. in case of HTTP the request method, URI, status code/status message and request parameter keys are captured. In addition to protocol specific fields, the infrastructure metadata fields are also captured, for e.g. the host name, container name/image, cloud infrastructure tags etc. for both the client and the server. For each unique combination of metadata fields metrics such as packet & byte counts, latency of L7 transaction and number of L7 transactions are captured.
The collectors ship only rolled up and summarized metrics which contain the metadata fields as described above back to AOC.