Mastering Kubernetes - Second Edition

Fluentd

Fluentd is a unified logging layer that sits between arbitrary data sources and arbitrary data sinks and makes sure that log messages can stream from A to B. Kubernetes comes with an add-on that has a Docker image that deploys the fluentd agent, which knows how to read various logs that are relevant to Kubernetes, such as Docker logs, etcd logs, and Kube logs. It also adds labels to each log message to make it easy for users to filter later by label. Here is a snippet from the fluentd-es-configmap.yaml file:

# Example:# 2016/02/04 06:52:38 filePurge: successfully removed file /var/etcd/data/member/wal/00000000000006d0-00000000010a23d1.wal<source>  type tail  # Not parsing this, because it doesn't have anything particularly useful to ...