k3s/docs/logging.md

# Logging

## Logging by Kubernetes Components
Kubernetes components, such as kubelet and apiserver, use the [glog](https://godoc.org/github.com/golang/glog) logging library.  Developer conventions for logging severity are described in [devel/logging.md](devel/logging.md).

## Logging in Containers
There are no Kubernetes-specific requirements for logging from within containers.  A
[search](https://www.google.com/?q=docker+container+logging) will turn up any number of articles about logging and
Docker containers.  However, we do provide an example of how to collect, index, and view pod logs [using Elasicsearch and Kibana](./getting-started-guides/logging.md)
Separated user, dev, and design docs. Renamed: logging.md -> devel/logging.m Renamed: access.md -> design/access.md Renamed: identifiers.md -> design/identifiers.md Renamed: labels.md -> design/labels.md Renamed: namespaces.md -> design/namespaces.md Renamed: security.md -> design/security.md Renamed: networking.md -> design/networking.md Added abbreviated user user-focused document in place of most moved docs. Added docs/README.md explains how docs are organized. Added short, user-oriented documentation on labels Added a glossary. Fixed up some links. 2014-10-16 21:45:16 +00:00			`# Logging`

			`## Logging by Kubernetes Components`
			`Kubernetes components, such as kubelet and apiserver, use the [glog](https://godoc.org/github.com/golang/glog) logging library. Developer conventions for logging severity are described in [devel/logging.md](devel/logging.md).`

			`## Logging in Containers`
			`There are no Kubernetes-specific requirements for logging from within containers. A`
			`[search](https://www.google.com/?q=docker+container+logging) will turn up any number of articles about logging and`
			`Docker containers. However, we do provide an example of how to collect, index, and view pod logs [using Elasicsearch and Kibana](./getting-started-guides/logging.md)`
Introduce some default log verbosity control Move a lot of common error logging into better buckets: glog.Errorf() - Always an error glog.Warningf() - Something unexpected, but probably not an error glog.V(0) - Generally useful for this to ALWAYS be visible to an operator * Programmer errors * Logging extra info about a panic * CLI argument handling glog.V(1) - A reasonable default log level if you don't want verbosity * Information about config (listening on X, watching Y) * Errors that repeat frequently that relate to conditions that can be corrected (pod detected as unhealthy) glog.V(2) - Useful steady state information about the service * Logging HTTP requests and their exit code * System state changing (killing pod) * Controller state change events (starting pods) * Scheduler log messages glog.V(3) - Extended information about changes * More info about system state changes glog.V(4) - Debug level verbosity (for now) * Logging in particularly thorny parts of code where you may want to come back later and check it 2014-09-18 10:46:14 +00:00