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1.2 additions for user-guide/

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John Mulhausen
2016-03-07 12:09:02 +00:00
parent e899d54a1b
commit f16668b45f
60 changed files with 2547 additions and 948 deletions
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docs/user-guide/connecting-applications.md
+18 -6
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@@ -12,7 +12,7 @@ By default, Docker uses host-private networking, so containers can talk to other
Coordinating ports across multiple developers is very difficult to do at scale and exposes users to cluster-level issues outside of their control. Kubernetes assumes that pods can communicate with other pods, regardless of which host they land on. We give every pod its own cluster-private-IP address so you do not need to explicitly create links between pods or mapping container ports to host ports. This means that containers within a Pod can all reach each other's ports on localhost, and all pods in a cluster can see each other without NAT. The rest of this document will elaborate on how you can run reliable services on such a networking model.
This guide uses a simple nginx server to demonstrate proof of concept. The same principles are embodied in a more complete [Jenkins CI application](http://blog.kubernetes.io/2015/07/strong-simple-ssl-for-kubernetes).
This guide uses a simple nginx server to demonstrate proof of concept. The same principles are embodied in a more complete [Jenkins CI application](http://blog.kubernetes.io/2015/07/strong-simple-ssl-for-kubernetes.html).
## Exposing pods to the cluster
@@ -43,8 +43,8 @@ This makes it accessible from any node in your cluster. Check the nodes the pod
```shell
$ kubectl create -f ./nginxrc.yaml
$ kubectl get pods -l app=nginx -o wide
my-nginx-6isf4 1/1 Running 0 2h e2e-test-beeps-minion-93ly
my-nginx-t26zt 1/1 Running 0 2h e2e-test-beeps-minion-93ly
my-nginx-6isf4 1/1 Running 0 2h e2e-test-beeps-node-93ly
my-nginx-t26zt 1/1 Running 0 2h e2e-test-beeps-node-93ly
```
Check your pods' IPs:
@@ -83,7 +83,7 @@ spec:
app: nginx
```
This specification will create a Service which targets TCP port 80 on any Pod with the `app=nginx` label, and expose it on an abstracted Service port (`targetPort`: is the port the container accepts traffic on, `port`: is the abstracted Service port, which can be any port other pods use to access the Service). View [service API object](http://kubernetes.io/v1.1/docs/api-reference/v1/definitions/#_v1_service) to see the list of supported fields in service definition.
This specification will create a Service which targets TCP port 80 on any Pod with the `app=nginx` label, and expose it on an abstracted Service port (`targetPort`: is the port the container accepts traffic on, `port`: is the abstracted Service port, which can be any port other pods use to access the Service). View [service API object](/docs/api-reference/v1/definitions/#_v1_service) to see the list of supported fields in service definition.
Check your Service:
```shell
@@ -289,7 +289,7 @@ Lets test this from a pod (the same secret is being reused for simplicity, the p
```shell
$ cat curlpod.yaml
vapiVersion: v1
apiVersion: v1
kind: ReplicationController
metadata:
name: curlrc
@@ -367,7 +367,7 @@ $ curl https://104.197.63.17:30645 -k
Lets now recreate the Service to use a cloud load balancer, just change the `Type` of Service in the nginx-app.yaml from `NodePort` to `LoadBalancer`:
```shell
$ kubectl delete rc, svc -l app=nginx
$ kubectl delete rc,svc -l app=nginx
$ kubectl create -f ./nginx-app.yaml
$ kubectl get svc nginxsvc
NAME CLUSTER_IP EXTERNAL_IP PORT(S) SELECTOR AGE
@@ -381,6 +381,18 @@ $ curl https://162.22.184.144 -k
The IP address in the `EXTERNAL_IP` column is the one that is available on the public internet. The `CLUSTER_IP` is only available inside your
cluster/private cloud network.
Note that on AWS, type `LoadBalancer` creates an ELB, which uses a (long)
hostname, not an IP. It's too long to fit in the standard `kubectl get svc`
output, in fact, so you'll need to do `kubectl describe service nginxsvc` to
see it. You'll see something like this:
```shell
> kubectl describe service nginxsvc
...
LoadBalancer Ingress: a320587ffd19711e5a37606cf4a74574-1142138393.us-east-1.elb.amazonaws.com
...
```
## What's next?
[Learn about more Kubernetes features that will help you run containers reliably in production.](/docs/user-guide/production-pods)