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simplifying instructions, removing redundant sections, fixing #59
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@arun-gupta
arun-gupta committed Jun 16, 2015
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221 changes: 103 additions & 118 deletions chapters/docker-kubernetes.adoc
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Expand Up @@ -116,17 +116,18 @@ NAME LABELS STATUS
+
[source, text]
----
> ./cluster/kubectl.sh get nodes
NAME LABELS STATUS
10.245.1.3 kubernetes.io/hostname=10.245.1.3 Ready
kubernetes> ./cluster/kubectl.sh get po
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED MESSAGE
kube-dns-v1-jnvez 172.17.0.2 10.245.1.3/10.245.1.3 k8s-app=kube-dns,kubernetes.io/cluster-service=true,version=v1 Running 6 minutes
skydns gcr.io/google_containers/skydns:2015-03-11-001 Running 4 minutes last termination: exit code 2
kube2sky gcr.io/google_containers/kube2sky:1.7 Running 4 minutes
etcd gcr.io/google_containers/etcd:2.0.9 Running 5 minutes
kube-scheduler-kubernetes-master kubernetes-master/ <none> Pending 2 seconds
kube-scheduler gcr.io/google_containers/kube-scheduler:d1f640dfb379f64daf3ae44286014821
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED MESSAGE
etcd-server-kubernetes-master kubernetes-master/ <none> Running 2 minutes
etcd-container gcr.io/google_containers/etcd:2.0.9 Running 2 minutes
kube-apiserver-kubernetes-master kubernetes-master/ <none> Running 2 minutes
kube-apiserver gcr.io/google_containers/kube-apiserver:465b93ab80b30057f9c2ef12f30450c3 Running 2 minutes
kube-dns-v1-lxdof 10.245.1.3/ k8s-app=kube-dns,kubernetes.io/cluster-service=true,version=v1 Pending 2 minutes
etcd gcr.io/google_containers/etcd:2.0.9
kube2sky gcr.io/google_containers/kube2sky:1.7
skydns gcr.io/google_containers/skydns:2015-03-11-001
kube-scheduler-kubernetes-master kubernetes-master/ <none> Running 2 minutes
kube-scheduler gcr.io/google_containers/kube-scheduler:d1f640dfb379f64daf3ae44286014821 Running 2 minutes
----
+
. Check the list of services running:
Expand Down Expand Up @@ -174,35 +175,54 @@ Any Service that a Pod wants to access must be created before the Pod itself, or
./cluster/kubectl.sh create -f ../../attendees/kubernetes/mysql-service.yaml
----
+
It uses the following configuration file:
+
[source, yaml]
----
id: mysql
kind: Service
apiVersion: v1beta3
metadata:
name: mysql
labels:
name: mysql
context: docker-k8s-lab
spec:
ports:
- port: 3306
selector:
name: mysql
labels:
name: mysql
----
+
. Check that the service is created:
+
[source, text]
----
> ./cluster/kubectl.sh get se
NAME LABELS SELECTOR IP(S) PORT(S)
kube-dns k8s-app=kube-dns,kubernetes.io/cluster-service=true,kubernetes.io/name=KubeDNS k8s-app=kube-dns 10.247.0.10 53/UDP
53/TCP
kubernetes component=apiserver,provider=kubernetes <none> 10.247.0.2 443/TCP
kubernetes-ro component=apiserver,provider=kubernetes <none> 10.247.0.1 80/TCP
mysql name=mysql name=mysql 10.247.82.83 3306/TCP
> ./cluster/kubectl.sh get se -l context=docker-k8s-lab
NAME LABELS SELECTOR IP(S) PORT(S)
mysql context=docker-k8s-lab,name=mysql name=mysql 10.247.141.208 3306/TCP
----
+
. When a Pod is run on a node, the kubelet adds a set of environment variables for each active Service.
Note that the label used during the creation is used to query the service.
+
When a Pod is run on a node, the kubelet adds a set of environment variables for each active Service.
+
It supports both Docker links compatible variables and simpler `{SVCNAME}_SERVICE_HOST` and `{SVCNAME}_SERVICE_PORT` variables, where the Service name is upper-cased and dashes are converted to underscores.
+
Our service name is ``mysql'' and so `MYSQL_SERVICE_HOST` and `MYSQL_SERVICE_PORT` variables are available to other pods.

TODO: Consider adding DNS support as explained at: https://github.com/GoogleCloudPlatform/kubernetes/blob/master/docs/services.md#dns
Send a Pull Request for https://github.com/javaee-samples/docker-java/issues/62[#62].

#### Start MySQL Replication Controller

. Start MySQL replication controller as:
+
[source, text]
----
> ./cluster/kubectl.sh create --v=5 -f ../../attendees/kubernetes/mysql.yaml
I0616 13:46:49.767091 4376 defaults.go:174] creating security context for container mysql
> ./cluster/kubectl.sh --v=5 create -f ../../attendees/kubernetes/mysql.yaml
I0616 19:41:55.441461 8346 defaults.go:174] creating security context for container mysql
replicationcontrollers/mysql
----
+
Expand All @@ -213,17 +233,19 @@ It uses the following configuration file:
kind: ReplicationController
apiVersion: v1beta3
metadata:
name: mysql-server
name: mysql
labels:
name: mysql-server
name: mysql
context: docker-k8s-lab
spec:
replicas: 1
selector:
name: mysql-server
name: mysql
template:
metadata:
labels:
name: mysql-server
name: mysql
context: docker-k8s-lab
spec:
containers:
- name: mysql
Expand All @@ -238,19 +260,29 @@ spec:
- name: MYSQL_ROOT_PASSWORD
value: supersecret
ports:
- containerPort: 3360
- containerPort: 3306
hostPort: 3306
----
+
Once again, the ``docker-k8s-lab'' label is used. This simplifies querying the created pods later on.
+
. Verify MySQL replication controller as:
+
[source, text]
----
> ./cluster/kubectl.sh get rc
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
kube-dns-v1 etcd gcr.io/google_containers/etcd:2.0.9 k8s-app=kube-dns,version=v1 1
kube2sky gcr.io/google_containers/kube2sky:1.7
skydns gcr.io/google_containers/skydns:2015-03-11-001
mysql-server mysql mysql:latest name=mysql-server 1
> ./cluster/kubectl.sh get rc -l context=docker-k8s-lab
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
mysql mysql mysql:latest name=mysql 1
----
+
. Check the status of MySQL pod as:
+
[source, text]
----
> ./cluster/kubectl.sh get po -l context=docker-k8s-lab
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED MESSAGE
mysql-7lq67 10.245.1.3/ context=docker-k8s-lab,name=mysql Pending About a minute
mysql mysql:latest
----

#### Start WildFly Replication Controller
Expand All @@ -259,8 +291,8 @@ mysql-server mysql mysql:latest n
+
[source, text]
----
> ./cluster/kubectl.sh --v=5 create -f ../../attendees/kubernetes/wildfly.yaml
I0605 16:25:41.990260 66897 defaults.go:174] creating security context for container wildfly
> ./cluster/kubectl.sh --v=5 create -f ../../attendees/kubernetes/wildfly.yaml
I0616 18:59:00.563099 7849 defaults.go:174] creating security context for container wildfly
replicationcontrollers/wildfly
----
+
Expand All @@ -274,6 +306,7 @@ metadata:
name: wildfly
labels:
name: wildfly
context: docker-k8s-lab
spec:
replicas: 1
selector:
Expand All @@ -282,27 +315,52 @@ spec:
metadata:
labels:
name: wildfly-server
context: docker-k8s-lab
spec:
containers:
- name: wildfly
image: arungupta/wildfly-mysql-javaee7:k8s
ports:
- containerPort: 8080
hostPort: 8080
----
+
. Verify WildFly replication controller as:
. Verify WildFly replication controller using ``docker-k8s-lab'' label as:
+
[source, text]
----
> ./cluster/kubectl.sh get rc
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
kube-dns-v1 etcd gcr.io/google_containers/etcd:2.0.9 k8s-app=kube-dns,version=v1 1
kube2sky gcr.io/google_containers/kube2sky:1.7
skydns gcr.io/google_containers/skydns:2015-03-11-001
mysql-server mysql mysql:latest name=mysql-server 1
wildfly wildfly arungupta/wildfly-mysql-javaee7:knetes name=wildfly-server 1
> ./cluster/kubectl.sh get rc -l context=docker-k8s-lab
CONTROLLER CONTAINER(S) IMAGE(S) SELECTOR REPLICAS
mysql mysql mysql:latest name=mysql 1
wildfly wildfly arungupta/wildfly-mysql-javaee7:k8s name=wildfly-server 1
----
+
. Check the status of WildFly pod as:
+
[source, text]
----
> ./cluster/kubectl.sh get pod -l context=docker-k8s-lab
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED MESSAGE
mysql-7lq67 10.245.1.3/ context=docker-k8s-lab,name=mysql Pending 3 minutes
mysql mysql:latest
wildfly-o0nw6 10.245.1.3/ context=docker-k8s-lab,name=wildfly-server Pending 45 seconds
wildfly arungupta/wildfly-mysql-javaee7:k8s
----

Make sure the status of both WildFly and MySQL pod is changed to ``running''. It will look like:

[source, text]
----
> ./cluster/kubectl.sh get pod -l context=docker-k8s-lab
POD IP CONTAINER(S) IMAGE(S) HOST LABELS STATUS CREATED MESSAGE
mysql-7lq67 172.17.0.9 10.245.1.3/10.245.1.3 context=docker-k8s-lab,name=mysql Running 14 minutes
mysql mysql:latest Running 10 minutes
wildfly-o0nw6 172.17.0.10 10.245.1.3/10.245.1.3 context=docker-k8s-lab,name=wildfly-server Running 11 minutes
wildfly arungupta/wildfly-mysql-javaee7:k8s Running 26 seconds
----

NOTE: Takes a while for all the pods to start. It took ~25 minutes on a 16 GB, i7 Mac OS X.

### Access Java EE Application

http://<pod_ip>:8080/employees/resources/employees
Expand All @@ -314,7 +372,7 @@ http://<pod_ip>:8080/employees/resources/employees

### Application Logs

. Login to the Minion-1 VM:
. Login to Minion-1 VM:
+
[source, text]
----
Expand Down Expand Up @@ -357,41 +415,13 @@ docker logs <CID>

### Delete Kubernetes Resources

. Delete WildFly repliation controller as:
+
[source, text]
----
> ./cluster/kubectl.sh --v=5 delete -f ../../attendees/kubernetes/wildfly.yaml
I0605 16:39:09.152694 67149 defaults.go:174] creating security context for container wildfly
replicationcontrollers/wildfly
----
+
. Delete MySQL replication controller as:
+
[source, text]
----
> ./cluster/kubectl.sh --v=5 delete -f ../../attendees/kubernetes/mysql.yaml
I0605 17:54:26.042191 67742 defaults.go:174] creating security context for container mysql
replicationcontrollers/mysql-server
----
+
. Delete MySQL service as:
+
[source, text]
----
> ./cluster/kubectl.sh --v=5 delete -f ../../attendees/kubernetes/mysql-service.yaml
services/mysql
----

Alternatively, all services and replication controllers can be assigned a label and deleted as:
Individual resources (service, replication controller, or pod) can be deleted by using `delete` command instead of `create` command. Alternatively, all services and replication controllers can be deleted using a label as:

[source, text]
----
kubectl delete -l services,pods name=docker-lab
kubectl delete -l se,po context=docker-k8s-lab
----

Send a PR for the last code: https://github.com/javaee-samples/docker-java/issues/59

### Stop Kubernetes Cluster

[source, text]
Expand Down Expand Up @@ -447,50 +477,5 @@ b1809bdabd9c gcr.io/google_containers/pause:0.8.0
+
. Log out of master.
#### Kubernetes Minion
. Check the minions:
+
[source, text]
----
kubernetes> ./cluster/kubectl.sh get minions
----
+
This is not giving the expected output and filed as https://github.com/GoogleCloudPlatform/kubernetes/issues/9271.
+
. Docker and Kubelet are running in minion and can be verified by logging in.
+
Log in to the minion as:
+
[source, text]
----
cluster> vagrant ssh minion-1
Last login: Thu Jun 4 19:30:03 2015 from 10.0.2.2
[vagrant@kubernetes-minion-1 ~]$
----
+
. Check the status of Docker:
+
[source, text]
----
[vagrant@kubernetes-minion-1 ~]$ sudo systemctl status docker
docker.service - Docker Application Container Engine
Loaded: loaded (/usr/lib/systemd/system/docker.service; enabled)
Active: active (running) since Thu 2015-06-04 19:29:44 UTC; 1h 24min ago
Docs: http://docs.docker.com
Main PID: 2651 (docker)
CGroup: /system.slice/docker.service
└─2651 /usr/bin/docker -d --selinux-enabled
Jun 04 20:53:41 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:41Z" level="info" msg="-job containers() = OK (0)"
Jun 04 20:53:41 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:41Z" level="info" msg="GET /containers/json"
Jun 04 20:53:41 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:41Z" level="info" msg="+job containers()"
Jun 04 20:53:41 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:41Z" level="info" msg="-job containers() = OK (0)"
Jun 04 20:53:42 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:42Z" level="info" msg="GET /containers/json"
Jun 04 20:53:42 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:42Z" level="info" msg="+job containers()"
Jun 04 20:53:42 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:42Z" level="info" msg="-job containers() = OK (0)"
Jun 04 20:53:46 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:46Z" level="info" msg="GET /version"
Jun 04 20:53:46 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:46Z" level="info" msg="+job version()"
Jun 04 20:53:46 kubernetes-minion-1 docker[2651]: time="2015-06-04T20:53:46Z" level="info" msg="-job version() = OK (0)"
----

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