Shulou(Shulou.com)06/03 Report--

First, one of the ways to create resources, create resources by command, understand the actions after the command runs, and summarize the origin of Pod names by viewing resources.

When we execute the command to create resources, the deployment controller will manage the pod through the replicaset controller. Let's analyze through an example, what does K8s do after we execute the command to create resources (rules can be found through its NAME)?

Run a deployment [root@master ~] # kubectl run test01-- image=nginx:latest-- run a nginx container, specifying the number of copies as 2 [root@master ~] # kubectl get deployments. # looking at the deployment controller NAME READY UP-TO-DATE AVAILABLE AGEtest01 2 deployment 22 48s#, we can see that the name of deployment is the test01 [root@master ~] # kubectl get replicasets. # then check the replicasets controller # Note: replicasets can be abbreviated to "rs" NAME DESIRED CURRENT READY AGEtest01-799bb6cd4d 222 119s#. You can see that the NAME of replicasets is appended with a string of ID numbers [root@master ~] # kubectl get pod # after the NAME of deployment. # check the nameNAME READY STATUS RESTARTS AGEtest01-799bb6cd4d-d88wd of pod. 1 Running 0 3m18stest01-799bb6cd4d-x8wpm 1 Running 0 3m18s# you can see that the NAME of the pod is appended with an ID after the above replicasets

At the same time, you can verify the above statement by viewing the details of each resource object, as follows:

[root@master ~] # kubectl describe deployments test01 # View the details of test01

The information returned is as follows, and you can see that a new replicasets controller is generated, as follows:

So, now look at its replicasets details, as follows:

Second, what do I need to do if I want client to access the deployed services? Where is the key point?

If you need client to access the services deployed by K8s, you need to create a service resource object whose type must be NodePort. The client contacts the proxy in the K8s cluster by accessing the port mapped by the resource object service in order to access the deployed services.

The implementation process is as follows: [root@master ~] # kubectl run test02-- image=nginx:latest-- port=80-- replicas=2# creates a deployment resource object based on nginx image, and maps port 80 of the container to the host [root@master ~] # kubectl expose deployment test02-- name=web01-- port=80-- type=NodePort# to create a service. Map port 80 of the deployed test02 to [root@master ~] # kubectl get svc web01 # View the information of the created web01 this service NAME TYPE CLUSTER-IP EXTERNAL-IP PORT (S) AGEweb01 NodePort 10.103.223.105 80:30230/TCP 86s#, you can see that the deployed service port is mapped to 30230 of the host

When the client accesses port 30230 of any node in the k8s cluster, it can access the home page of the service, as follows:

Third, build registry warehouse. Based on the nginx custom image, change the default access interface to: hello K8s. This is version 1.10. And run a Deployment resource object based on this image, the number of replicas is 4. # Building a registry warehouse And the nodes in the cluster are assigned to the private warehouse [root@master ~] # docker run-tid-- name registry-p 5000name registry 5000-- restart always registry:latest [root@master ~] # vim / usr/lib/systemd/system/docker.service # to edit the configuration file ExecStart=/usr/bin/dockerd-H unix://-- insecure-registry 192.168.20.6 name registry 500legs to send the modified configuration file to other sections in the k8s cluster Click [root@master ~] # scp / usr/lib/systemd/system/docker.service root@node01:/usr/lib/systemd/system/ [root@master ~] # scp / usr/lib/systemd/system/docker.service root@node02:/usr/lib/systemd/system/# all nodes that have changed the docker configuration file need to do the following In order to change the effective [root@master ~] # systemctl daemon-reload [root@master ~] # systemctl restart docker# to create a custom image [root@master ~] # vim DockerfileFROM nginx:latestADD index.html / usr/share/nginx/html/ [root@master ~] # echo "hello k8s" > index.html [root@master ~] # docker build-t 192.168.20.6:5000/nginx:1.10. [root@master ~] # docker push 192.168.20.6 systemctl restart docker# 5000 / nginx:1.10 # upload to private repository # run a Deployment resource object based on a custom image The number of replicas is 4. [root@master ~] # kubectl run test03-- image=192.168.20.6:5000/nginx:1.10-- port=80-- replicas=4 [root@master ~] # kubectl get pod-o wide | grep test03 | awk'{print $6}'# check the IP addresses of the four replicas 10.244.2.2010.244.1.1810.244.1.1910.244.2.2" then visit any of the four IP within the K8s cluster to see the services they provide. As follows: # access test [root@master ~] # curl 10.244.2.21 hello k8s [root@master ~] # curl 10.244.2.20hello k8s 4. Update and expand the above Deployment resource objects, and update the number of replicas to 6. The image is still a custom image, and the default access interface is changed to: Hello update.# updates the image and uploads it to the private repository [root@master ~] # echo "Hello update" > index.html [root@master ~] # docker build-t 192.168.20.6:5000/nginx:2.20. [root@master ~] # docker push 192.168.20.6:5000/nginx:2.20 # updates the resource object Expand [root@master ~] # kubectl set image deployment test03 test03=192.168.20.6:5000/nginx:2.20 & & kubectl scale deployment test03-- replicas=6# to view the IP address of pod [root@master ~] # kubectl get pod-o wide | grep test03 | awk'{print $6} '10.244.2410.244.2.2210.244.1.2110.244.2.2310.244.1.2210.244.1.2 access test [root@master ~] # curl 10.244.1.20Hello update [root@master ~] # curl 10.244.1.22Hello update V Roll back this Deployment resource object Check the content of the access interface and the number of replicas for the last version of the verification. [root@master ~] # kubectl rollout undo deployment test03 # perform rollback operation [root@master ~] # kubectl get pod-o wide | grep test03 | wc-l # check the number of replicas or 6 root@master access tests [root@master ~] # kubectl get pod-o wide | grep test03 | awk'{print $6} '10.244.1.2310.244.2.2710.244.1.2410.244.1.2510.244.1.2510.244.2.2610.244.25 [root @ master ~] # curl 10.244.2.25hello k8s [root@master ~] # curl 10.244.2.26hello k8s

-this is the end of this article. Thank you for reading-

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