What is event in OpenShift?
Events in OpenShift Container Platform are modeled based on events that happen to API objects in an OpenShift Container Platform cluster. Events allow OpenShift Container Platform to record information about real-world events in a resource-agnostic manner.
How does OpenShift networking work?
OpenShift Container Platform uses a software-defined networking (SDN) approach to provide a unified cluster network that enables communication between pods across the OpenShift Container Platform cluster. Each project receives a unique Virtual Network ID (VNID) that identifies traffic from pods assigned to the project.
How do you check events in Kubernetes?
For the most part, events are easy to see when you are trying to debug issues for a specific resource. Using kubectl describe pod for example will show events at the end of the output for the pod. Only events that have occurred relatively recently (within a few hours) will appear.
How does DNS work in OpenShift?
1. DNS Operator in OpenShift 4. The DNS Operator implements the dns API from the operator.openshift.io API group. The operator deploys CoreDNS using a DaemonSet, creates a Service for the DaemonSet, and configures the kubelet to instruct pods to use the CoreDNS Service IP for name resolution.
How long do Kubernetes events last?
Events have a high volume of activity compared to other objects in the Kubernetes. By default, events have a 1-hour life span and a separate etcd cluster is recommended to ensure scalability.
Is there any way to check the consolidated events logs of all pods that is running in OpenShift cluster through CLI or dashboard?
To view cluster logs:
- In the OpenShift Container Platform console, navigate to Workloads → Pods.
- Select the openshift-logging project from the drop-down menu.
- Click one of the logging collector pods with the fluentd prefix.
- Click Logs.
What is OpenShift route?
A route allows you to host your application at a public URL. It can either be secure or unsecured, depending on the network security configuration of your application. The following procedure describes how to create a simple HTTP-based route to a web application, using the hello-openshift application as an example.
What exactly is Software Defined networking?
Software-Defined Networking (SDN) is an approach to networking that uses software-based controllers or application programming interfaces (APIs) to communicate with underlying hardware infrastructure and direct traffic on a network.
How do Kubernetes events work?
Kubernetes events are objects that show you what is happening inside a cluster, such as what decisions were made by the scheduler or why some pods were evicted from the node. All core components and extensions (operators) may create events through the API Server.
Where are Kubernetes events stored?
etcd
Why We Care About Kubernetes Events and the cause. This data is typically stored in etcd and made available when you run certain kubectl commands. These events help understand what happened behind the scenes when a particular entity entered a specific state.
What is a DNS operator?
The DNS Operator. The DNS Operator deploys and manages CoreDNS to provide a name resolution service to pods that enables DNS-based Kubernetes Service discovery in OpenShift. The operator tries to be useful out of the box by creating a working default deployment based on the cluster’s configuration.
