IT Cloud. Eugeny Shtoltc
Читать онлайн книгу.
this can be done through the UI. Next to the menu, click on the drop-down list and create a separate project. In the Kubernetes Engine section, choose to create a cluster. Let's give the name, 2CPU, the europe-north-1 zone (the data center in Finland is closest to St. Petersburg) and the latest version of Kubernetes. After creating the cluster, click on connect and select Cloud Shell. To create through the API, click the button in the upper right corner to display the console panel and enter in it:
gcloud container clusters create mycluster –zone europe-north1-a
After a while, it took me two and a half minutes, 3 virtual machines will be raised, the operating system is installed on them and the disk is mounted. Let's check:
esschtolts @ cloudshell: ~ (essch) $ gcloud container clusters list –filter = name = mycluster
NAME LOCATION MASTER_IP MACHINE_TYPE NODE_VERSION NUM_NODES STATUS
mycluster europe-north1-a 35.228.37.100 n1-standard-1 1.10.9-gke.5 3 RUNNING
esschtolts @ cloudshell: ~ (essch) $ gcloud compute instances list
NAME MACHINE_TYPE EXTERNAL_IP STATUS
gke-mycluster-default-pool-43710ef9-0168 n1-standard-1 35.228.73.217 RUNNING
gke-mycluster-default-pool-43710ef9-39ck n1-standard-1 35.228.75.47 RUNNING
gke-mycluster-default-pool-43710ef9-g76k n1-standard-1 35.228.117.209 RUNNING
Let's connect to the virtual machine:
esschtolts @ cloudshell: ~ (essch) $ gcloud projects list
PROJECT_ID NAME PROJECT_NUMBER
agile-aleph-203917 My First Project 546748042692
essch app 283762935665
esschtolts @ cloudshell: ~ (essch) $ gcloud container clusters get-credentials mycluster \
–-zone europe-north1-a \
–-project essch
Fetching cluster endpoint and auth data.
kubeconfig entry generated for mycluster.
We don't have a cluster yet:
esschtolts @ cloudshell: ~ (essch) $ kubectl get pods
No resources found.
Let's create a cluster:
esschtolts @ cloudshell: ~ (essch) $ kubectl run Nginx –image = Nginx –replicas = 3
deployment.apps "Nginx" created
Let's check its composition:
esschtolts @ cloudshell: ~ (essch) $ kubectl get deployments –selector = run = Nginx
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
Nginx 3 3 3 3 14s
esschtolts @ cloudshell: ~ (essch) $ kubectl get pods –selector = run = Nginx
NAME READY STATUS RESTARTS AGE
Nginx-65899c769f-9whdx 1/1 Running 0 43s
Nginx-65899c769f-szwtd 1/1 Running 0 43s
Nginx-65899c769f-zs6g5 1/1 Running 0 43s
Let's make sure that all three replicas of the cluster are distributed evenly across all three nodes:
esschtolts @ cloudshell: ~ (essch) $ kubectl describe pod Nginx-65899c769f-9whdx | grep Node:
Node: gke-mycluster-default-pool-43710ef9-g76k / 10.166.0.5
esschtolts @ cloudshell: ~ (essch) $ kubectl describe pod Nginx-65899c769f-szwtd | grep Node:
Node: gke-mycluster-default-pool-43710ef9-39ck / 10.166.0.4
esschtolts @ cloudshell: ~ (essch) $ kubectl describe pod Nginx-65899c769f-zs6g5 | grep Node:
Node: gke-mycluster-default-pool-43710ef9-g76k / 10.166.0.5
Now let's install the load balancer:
esschtolts @ cloudshell: ~ (essch) $ kubectl expose Deployment Nginx –type = "LoadBalancer" –port = 80
service "Nginx" exposed
Let's check that it was created:
esschtolts @ cloudshell: ~ (essch) $ kubectl expose Deployment Nginx –type = "LoadBalancer" –port = 80
service "Nginx" exposed
esschtolts @ cloudshell: ~ (essch) $ kubectl get svc –selector = run = Nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT (S) AGE
Nginx LoadBalancer 10.27.245.187 pending> 80: 31621 / TCP 11s
esschtolts @ cloudshell: ~ (essch) $ sleep 60;
esschtolts @ cloudshell: ~ (essch) $ kubectl get svc –selector = run = Nginx
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT (S) AGE
Nginx LoadBalancer 10.27.245.187 35.228.212.163 80: 31621 / TCP 1m
Let's check its work:
esschtolts @ cloudshell: ~ (essch) $ curl 35.228.212.163:80 2> \ dev \ null | grep h1
<h1> Welcome to Nginx! </ h1>
In order not to copy the full names every time, save them in variables (more about the JSONpath format in the Go documentation: https://golang.org/pkg/text/template/#pkg-overview):
esschtolts @ cloudshell: ~ (essch) $ pod1 = $ (kubectl get pods -o jsonpath = {. items [0] .metadata.name});
esschtolts @ cloudshell: ~ (essch) $ pod2 = $ (kubectl get pods -o jsonpath = {. items [1] .metadata.name});
esschtolts @ cloudshell: ~ (essch) $ pod3 = $ (kubectl get pods -o jsonpath = {. items [2] .metadata.name});
esschtolts @ cloudshell: ~ (essch) $ echo $ pod1 $ pod2 $ pod3
Nginx-65899c769f-9whdx Nginx-65899c769f-szwtd Nginx-65899c769f-zs6g5
Let's change the pages in each POD by copying the unique pages to each replica, and check the balancing by checking the distribution of requests across the POD:
esschtolts @ cloudshell: ~ (essch) $ echo 1> test.html;
esschtolts @ cloudshell: ~ (essch) $ kubectl cp test.html $ {pod1}: / usr / share / Nginx / html / index.html
esschtolts @ cloudshell: ~ (essch) $ echo 2> test.html;
esschtolts @ cloudshell: ~ (essch) $ kubectl cp test.html $ {pod2}: / usr / share / Nginx / html / index.html
esschtolts @ cloudshell: ~ (essch) $ echo 3> test.html;
esschtolts @ cloudshell: ~ (essch) $ kubectl cp test.html $ {pod3}: / usr / share / Nginx / html / index.html
esschtolts @ cloudshell: ~ (essch) $ curl 35.228.212.163:80 && curl 35.228.212.163:80 && curl 35.228.212.163:80
3
2
one
esschtolts @ cloudshell: ~ (essch) $ curl 35.228.212.163:80 && curl 35.228.212.163:80 && curl 35.228.212.163:80
3
one
one
Let's check the failover of the cluster by deleting one POD:
esschtolts @ cloudshell: ~ (essch) $ kubectl delete pod $ {pod1} && kubectl get pods && sleep 10 && kubectl get pods
pod "Nginx-65899c769f-9whdx" deleted
NAME READY STATUS RESTARTS AGE
Nginx-65899c769f-42rd5 0/1 ContainerCreating 0 1s
Nginx-65899c769f-9whdx 0/1 Terminating 0 54m
Nginx-65899c769f-szwtd 1/1 Running 0 54m
Nginx-65899c769f-zs6g5 1/1 Running 0 54m
NAME READY STATUS RESTARTS AGE
Nginx-65899c769f-42rd5 1/1 Running 0 12s
Nginx-65899c769f-szwtd 1/1 Running 0 55m
Nginx-65899c769f-zs6g5 1/1 Running