Shulou(Shulou.com)05/31 Report--

This article mainly introduces the use of kubernetes skills, has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, the following let the editor take you to understand it.

One: get the IP of Pod in the container

ApiVersion: v1

Kind: ReplicationController

Metadata:

Name: world-v2

Spec:

Replicas: 3

Selector:

App: world-v2

Template:

Metadata:

Labels:

App: world-v2

Spec:

Containers:

-name: service

Image: test

Env:

-name: POD_IP

ValueFrom:

FieldRef:

FieldPath: status.podIP

Ports:

-name: service

ContainerPort: 777

The container's IP can be obtained directly by using the POD_IP environment variable in the container, which directly refers to the status field of the resource.

Second: obtain the host name, namespace, etc., in Pod

ApiVersion: v1

Kind: Pod

Metadata:

Name: dapi-test-pod

Spec:

Containers:

-name: test-container

Image: busybox

Command: ["/ bin/sh", "- c", "env"]

Env:

-name: MY_NODE_NAME

ValueFrom:

FieldRef:

FieldPath: spec.nodeName

-name: MY_POD_NAME

ValueFrom:

FieldRef:

FieldPath: metadata.name

-name: MY_POD_NAMESPACE

ValueFrom:

FieldRef:

FieldPath: metadata.namespace

-name: MY_POD_IP

ValueFrom:

FieldRef:

FieldPath: status.podIP

-name: HOST_IP

ValueFrom:

FieldRef:

FieldPath: status.hostIP

-name: MY_POD_SERVICE_ACCOUNT

ValueFrom:

FieldRef:

FieldPath: spec.serviceAccountName

RestartPolicy: Never

This tip complements the first item to get the podIP, all in the same way, except that more reference fields are listed. Referring to the pod definition below, there is a {.spec.nodeName} field in each pod. Through fieldRef and environment variables, the host name of the host can be obtained in Pod (access to the environment variable MY_NODE_NAME).

Third, specify the startup parameters of the container

We can specify startup parameters for containers in Pod using command for containers:

Command: ["/ bin/bash", "- c", "bootstrap.sh"]

Defined as an array, all commands use the same CMD configuration as in Dockerfile, but one difference is that bootsttap.sh must have executable permissions, otherwise the container will make an error when it starts.

Fourth: synchronize the time in the container with the host

The time zone in many of the containers we downloaded is GMT, which is 8 hours behind Beijing time, which will cause the creation time of logs and files in the container to be inconsistent with the actual time zone. There are two ways to solve this problem:

1. Modify the time zone profile in the mirror

two。 Mount the host's time zone configuration file / etc/localtime into the container using volume

The second method is relatively simple. There is no need to redo the image, just add the following configuration to the yaml file of the application:

VolumeMounts:

-name: host-time

MountPath: / etc/localtime

ReadOnly: true

Volumes:

-name: host-time

HostPath:

Path: / etc/localtime

Five: kubectl command completion

# yum install-y bash-completion

# source / usr/share/bash-completion/bash_completion

# source

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.