apiVersion: apps / v1

kind: Deployment

metadata:

name: Nginxlamp

spec:

selector:

matchLabels:

app: lamp

replicas: 1

template:

metadata:

labels:

app: lamp

spec:

containers:

– name: lamp

image: mattrayner / lamp: latest-1604-php5

ports:

– containerPort: 80

esschtolts @ cloudshell: ~ / bitrix (essch) $ cat loadbalancer.yaml

apiVersion: v1

kind: Service

metadata:

name: frontend

spec:

type: LoadBalancer

ports:

– name: front

port: 80

targetPort: 80

selector:

app: lamp

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get pods

NAME READY STATUS RESTARTS AGE

Nginxlamp-7fb6fdd47b-jttl8 2/2 Running 0 3m

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get svc

NAME TYPE CLUSTER-IP EXTERNAL-IP PORT (S) AGE

frontend LoadBalancer 10.55.242.137 35.228.73.217 80: 32701 / TCP, 8080: 32568 / TCP 4m

kubernetes ClusterIP 10.55.240.1 none> 443 / TCP 48m

Now we can create identical copies of our clusters, for example, for Production and Develop, but balancing will not work as expected. The balancer will find PODs by label, and PODs in both production and Developer clusters correspond to this label. Also, placing clusters in different projects will not be an obstacle. Although, for many tasks, this is a big plus, but not in the case of a cluster for developers and production. The namespace is used to delimit the scope. We use them discreetly, when we list PODs without specifying a scope, we are displayed by default , but the PODs are not taken out of the system scope:

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get namespace

NAME STATUS AGE

default Active 5h

kube-public Active 5h

kube-system Active

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get pods –namespace = kube-system

NAME READY STATUS RESTARTS AGE

event-exporter-v0.2.3-85644fcdf-tdt7h 2/2 Running 0 5h

fluentd-gcp-scaler-697b966945-bkqrm 1/1 Running 0 5h

fluentd-gcp-v3.1.0-xgtw9 2/2 Running 0 5h

heapster-v1.6.0-beta.1-5649d6ddc6-p549d 3/3 Running 0 5h

kube-dns-548976df6c-8lvp6 4/4 Running 0 5h

kube-dns-548976df6c-mcctq 4/4 Running 0 5h

kube-dns-autoscaler-67c97c87fb-zzl9w 1/1 Running 0 5h

kube-proxy-gke-bitrix-default-pool-38fa77e9-0wdx 1/1 Running 0 5h

kube-proxy-gke-bitrix-default-pool-38fa77e9-wvrf 1/1 Running 0 5h

l7-default-backend-5bc54cfb57-6qk4l 1/1 Running 0 5h

metrics-server-v0.2.1-fd596d746-g452c 2/2 Running 0 5h

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get pods –namespace = default

NAMEREADY STATUS RESTARTS AGE

Nginxlamp-b5dcb7546-g8j5r 1/1 Running 0 4h

Let's create a scope:

esschtolts @ cloudshell: ~ / bitrix (essch) $ cat namespace.yaml

apiVersion: v1

kind: Namespace

metadata:

name: development

labels:

name: development

esschtolts @ cloudshell: ~ (essch) $ kubectl create -f namespace.yaml

namespace "development" created

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl get namespace –show-labels

NAME STATUS AGE LABELS

default Active 5h none>

development Active 16m name = development

kube-public Active 5h none>

kube-system Active 5h none>

The essence of working with scope is that for specific clusters we set the scope and we can execute commands specifying it, while they will apply only to them. At the same time, except for the keys in commands such as kubectl get pods I do not appear in the scope, therefore the configuration files of controllers (Deployment, DaemonSet and others) and services (LoadBalancer, NodePort and others) do not appear, allowing them to be seamlessly transferred between the scope, which especially relevant for the development pipeline: developer server, test server, and production server. Scopes are set in the cluster context file $ HOME / .kube / config using the kubectl config view command . So, in my cluster context entry, the scope entry does not appear (default is default ):

– context:

cluster: gke_essch_europe-north1-a_bitrix

user: gke_essch_europe-north1-a_bitrix

name: gke_essch_europe-north1-a_bitrix

You can see something like this:

esschtolts @ cloudshell: ~ / bitrix (essch) $ kubectl config view -o jsonpath = '{. contexts [4]}'

{gke_essch_europe-north1-a_bitrix {gke_essch_europe-north1-a_bitrix gke_essch_europe-north1-a_bitrix []}}

Let's create a new context for this user and cluster:

esschtolts @ cloudshell: ~ (essch) $ kubectl config set-context dev \