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

What is the new function of Kubernetes1.12, many novices are not very clear about this, in order to help you solve this problem, the following editor will explain for you in detail, people with this need can come to learn, I hope you can gain something.

Several major version updates of Kubernetes in 2018

Whether you are a developer using Kubernetes or an administrator responsible for operating a cluster, you should be aware of the new features and problem fixes in Kubernetes 1.12.

Kubernetes 1.12 contains 38 functions. Let's take a look at some bright spots.

Kubelet certificate rotation

The Kubelet certificate rotation function has now entered the beta state. This feature automatically renews the key and the kubelet API server's certificate when the current certificate expires.

Network policies: CIDR selectors and egress rules

Two previous beta functions are now in stable state: one is the ipBlock selector, which allows you to specify ingress/egress rules based on the network address in the CIDR notation. The second can filter traffic leaving the pod by specifying egress rules. The following example illustrates the use of these two features:

Egress and ipBlock used to be beta functions, and they are already in the official network policy document of Kubernetes.

Mount namespace propagation

Mount namespace propagation, that is, mount volume rshared, so that any mount in the container can be reflected in the root (= host) mount namespace, which is now in stable state.

Create Taint Nodes by condition

In Kubernetes1.8, this feature was an earlier version of alpha, and now it has been upgraded to beta. By enabling its featureflag, the node controller can create a taints based on node conditions and have the scheduler filter nodes based on taints rather than conditions.

Horizontal pod automatic extender with custom metrics

Although support for custom metrics in HPA has always been beta status, version 1.12 adds various enhancements, such as the ability to select metrics based on the tags available in the monitoring pipeline.

RuntimeClass

RuntimeClass is a new cluster-wide resource that "represents container runtime properties to the control plane". In other words, it allows users to select and configure (each pod) a specific container runtime (such as Docker, RKT, or Virtlet) by providing runtimeClass in PodSpec. This feature is still in the early alpha stage.

Resource quota priority

Resource quotas allow administrators to limit resource consumption in namespaces. This feature is especially useful when multiple tenants (users / teams) share available computing and storage resources in the cluster. The beta version of resource quota priority allows administrators to adjust the allocation of resources within a namespace by determining the scope of quotas based on the PriorityClass of pod.

Volume snapshot

One of the most exciting storage features in Kubernetes 1.12 is persistent volume snapshots (although it is still in the alpha phase). This feature allows users to create and restore snapshots at a specific point in time supported by any CSI storage provider. This update adds three new API resources as part of this feature:

VolumeSnapshotClass defines how to configure snapshots of existing volumes

VolumeSnapshotContent represents an existing snapshot

VolumeSnapshot allows users to request new snapshots of persistent volumes

Here is an example:

Topology aware dynamic configuration

Another storage-related feature, topology-aware dynamic configuration. This feature was first introduced in Kubernetes 1.11 and promoted to the beta state in 1.12. It addresses some of the limitations of dynamically configuring volumes in a cluster that spans multiple regions, where the back end of single-area storage is not globally accessible from all nodes.

Enhanced support for Azure

In Kubernetes 1.12, there are two enhancements to running Kubernetes in Azure:

Cluster auto-scaling

Azure's cluster auto-scaler support has been upgraded to a stable version. This will allow the number of Azure nodes in the Kubernetes cluster to be automatically expanded based on global resources.

Azure availability zone support

Kubernetes 1.12 added alpha support for the Azure availability zone (AZ). The nodes in the availability zone are labeled failure-domain.beta.kubernetes.io/zone=- and add a topology-aware configuration for the Azure managed disk storage class.

Is it helpful for you to read the above content? If you want to know more about the relevant knowledge or read more related articles, please follow the industry information channel, thank you for your support.

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.