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Use example syncer tags instead of hard-coded examples in doc

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Janet Kuo
2015-07-20 15:46:20 -07:00
parent 2bd53119b1
commit 180798cfa4
22 changed files with 306 additions and 104 deletions
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44
docs/getting-started-guides/logging.md
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@@ -58,20 +58,24 @@ This diagram shows four nodes created on a Google Compute Engine cluster with th
To help explain how cluster level logging works let’s start off with a synthetic log generator pod specification [counter-pod.yaml](../../examples/blog-logging/counter-pod.yaml):
<!-- BEGIN MUNGE: EXAMPLE ../../examples/blog-logging/counter-pod.yaml -->
```yaml
apiVersion: v1
kind: Pod
metadata:
name: counter
namespace: default
spec:
containers:
- name: count
image: ubuntu:14.04
args: [bash, -c,
'for ((i = 0; ; i++)); do echo "$i: $(date)"; sleep 1; done']
apiVersion: v1
kind: Pod
metadata:
name: counter
spec:
containers:
- name: count
image: ubuntu:14.04
args: [bash, -c,
'for ((i = 0; ; i++)); do echo "$i: $(date)"; sleep 1; done']
```
[Download example](../../examples/blog-logging/counter-pod.yaml)
<!-- END MUNGE: EXAMPLE -->
This pod specification has one container which runs a bash script when the container is born. This script simply writes out the value of a counter and the date once per second and runs indefinitely. Let’s create the pod in the default
namespace.
@@ -152,7 +156,9 @@ We’ve lost the log lines from the first invocation of the container in this po
When a Kubernetes cluster is created with logging to Google Cloud Logging enabled, the system creates a pod called `fluentd-cloud-logging` on each node of the cluster to collect Docker container logs. These pods were shown at the start of this blog article in the response to the first get pods command.
This log collection pod has a specification which looks something like this [fluentd-gcp.yaml](http://releases.k8s.io/HEAD/cluster/saltbase/salt/fluentd-gcp/fluentd-gcp.yaml):
This log collection pod has a specification which looks something like this:
<!-- BEGIN MUNGE: EXAMPLE ../../cluster/saltbase/salt/fluentd-gcp/fluentd-gcp.yaml -->
```yaml
apiVersion: v1
@@ -163,19 +169,31 @@ metadata:
spec:
containers:
- name: fluentd-cloud-logging
image: gcr.io/google_containers/fluentd-gcp:1.6
image: gcr.io/google_containers/fluentd-gcp:1.9
resources:
limits:
cpu: 100m
memory: 200Mi
env:
- name: FLUENTD_ARGS
value: -qq
volumeMounts:
- name: varlog
mountPath: /varlog
- name: containers
mountPath: /var/lib/docker/containers
volumes:
- name: varlog
hostPath:
path: /var/log
- name: containers
hostPath:
path: /var/lib/docker/containers
```
[Download example](../../cluster/saltbase/salt/fluentd-gcp/fluentd-gcp.yaml)
<!-- END MUNGE: EXAMPLE -->
This pod specification maps the directory on the host containing the Docker log files, `/var/lib/docker/containers`, to a directory inside the container which has the same path. The pod runs one image, `gcr.io/google_containers/fluentd-gcp:1.6`, which is configured to collect the Docker log files from the logs directory and ingest them into Google Cloud Logging. One instance of this pod runs on each node of the cluster. Kubernetes will notice if this pod fails and automatically restart it.
We can click on the Logs item under the Monitoring section of the Google Developer Console and select the logs for the counter container, which will be called kubernetes.counter_default_count. This identifies the name of the pod (counter), the namespace (default) and the name of the container (count) for which the log collection occurred. Using this name we can select just the logs for our counter container from the drop down menu: