Rancher User Install Kato

This article is for users who are using Rancher or have some knowledge of Rancher

Rancher, a successful open source project in the Kubernetes ecosystem, is positioned as “Run Kubernetes Everywhere”. Rancher can help developers quickly build cloud, edge, and end multi-dimensional Kubernetes clusters, and provide a UI-based management system for multiple cluster resources.

Kato positions “Enterprise Application Lifecycle Management”, similar to Rancher’s positioning statement should be “Run Application Everywhere”. Kato open source users have always faced a flaw, that is, the open source version of Kato does not provide for cluster monitoring and visual management. Therefore, combining Rancher is a solution in an open source scenario. For Rancher users, you may try to use Kato to manage your applications, and you will feel that it is not as efficient and simple as Rancher. By reading Kato related documents, you will find Kato’s unique product charm in serving enterprise application development, application operation and maintenance, and application delivery.

Next, it will take you to complete the installation of Kato system on Rancher.

Prerequisites

  1. Have a stable and usable Rancher environment, if you haven’t yet, you can refer to Rancher Installation and Deployment Document
  2. NFS client. If it is not installed, you can refer to:
    # CentOS system
    yum install -y nfs-utils
    # Ubuntu/Debian system
    apt install -y nfs-common
    
  3. The Kubernetes cluster has at least 4GB of free scheduling memory
  4. Kubernetes version is 1.13 and above
  5. The Kubernetes cluster has at least one node whose port 80/443 is not occupied

Start Installation

Add Kato Operator to the App Store

Add Kato Operator to Rancher’s App Store.

  1. In the App Store page, click Add App Store

  2. Enter Name (such as Kato-Operator) and Store URL address Enter https://github.com/gridworkz/kato-operator

Rancher will search for the Helm Chart that exists in the designated code repository. Due to domestic network reasons, use the address of kato-operator in gitee.

  1. Helm version select Helm v3

Kato-operator chart uses Helm v3 specification definition, so Helm v3 version must be selected.

  1. Click Create to complete the application store addition.

  2. Go back to the App Store page and click Start

  3. Click Refresh, after Rancher synchronization is complete, you can see the newly added Kato Operator.

Install Kato Operator

Start Kato Operator in Rancher.

  1. Click the identified kato-operator Chart to start Chart installation.

  2. Modify Namespace to rbd-system

Note that the current namespace can only be set to rbd-system, and install it according to the default configuration of kato-operator Chart.

  1. Click Start, it will jump to the application list page and wait for the status of kato-operator to become Active.

This process will obtain the relevant image of kato-operator from the public network, so its startup time greatly depends on your network environment.

Visit the Kato installation UI to improve the cluster configuration

After kato-operator is started, it will expose 30008 to provide UI display service for cluster configuration and installation process. So please visit Host IP:30008 to enter the Kato Operator UI page.

The configuration items include mirror repository configuration, database configuration and storage configuration. Please consider whether to provide the above services according to the actual situation of your environment (we recommend self-service for high-availability production environments). Of course, Kato will automatically install the above services by default.

The other two key configurations are the choice of gateway node and build node. By default, Kato will automatically select a suitable management node for Kubernetes. The gateway node installs the rbd-gateway gateway service, so it needs to occupy key ports such as 80, 443. As the node for Kato to build the image, it is best to choose a node with sufficient storage and computing resources. If the above two configuration items do not get the default values, for example, when there are no free nodes with port 80 in your cluster, you may need to do the following:

  1. Use the IP address to search for other available nodes and select.
  2. If there are no available nodes in the cluster, for example, you only have one node and have installed Ingress Controller, then you can modify the hostNetwork of Ingress Controller to false, or change its port to a port other than 80, 443 . Then re-install Kato. If there are multiple nodes, consider expelling the Ingress Controller from a node and letting out port resources for Kato to use.

After completing the configuration, you can click Configuration complete and start installation. During the installation process, Kato will obtain all required images and upload them to the local mirror repository, and then start all Kato components. This process is about 20 minutes, depending on your network environment.

Rancher-based Kato operation and maintenance reference

During the installation and use of Kato, Rancher can be used to operate and maintain Kato. For example, View the running status and logs of each component of Kato, and Expand each component of Kato as needed.

View the running status and logs of each component of Kato

On the workload page, find the namespace rbd-system to view the status, events and logs of each component of Kato. It can also monitor the workload of a certain component in real time, including CPU, memory, network packets, etc. If a component is abnormal, you can use the above information to troubleshoot; if necessary, you can upload it to Community, or submit Issues to Kato-Operator

Expand Kato components on demand

When the load of a Kato component is too high, you can use Rancher to increase the number of copies of the component and share some load; relatively, you can use Rancher to reduce the number of copies of the Kato component.

When you need to troubleshoot Kato components, you may need to modify the startup parameters or environment variables of the components. At this time, you can use Rancher to modify.

Advantages of Rancher Users Using Kato

No need to deeply learn how to use Kubernetes resources

Kato uses the cloud native application model to provide users with an intelligent and simple application development management model. Whether it is a simple application or a complex microservice architecture, the entire development and deployment process does not require developers to learn Kubernetes-related knowledge in depth.

Standard cloud-native 12-element application management model

You may have heard of the 12 elements of cloud native as the current recommended cloud native application development model. The Kato application model fully implements the 12 elements of cloud native. Using Kato will naturally make your code meet the cloud native requirements.

From source code to cloud

Common development languages ​​(Java, PHP, Python, Golang, NodeJS, .NetCore) do not need to define Dockerfile, do not need to define Kubernetes deployment method to complete continuous construction and continuous deployment.

Standard application multi-cluster delivery

Kato provides a variety of ways for developers to quickly deliver applications in multiple clusters and multiple environments to obtain a SaaS-based application delivery experience.

Microservice architecture

Kato has a built-in ServiceMesh micro-service architecture governance framework. All deployed components are managed according to the micro-service governance ideas, and the micro-service governance functions are available out of the box.

Common Problems

Can Rancher’s deployed applications be directly taken over by Kato

This question is the question of most users. We hope that Kato can automatically take over the applications deployed by Rancher. Unfortunately, because Rancher, the same type of platform, currently does not follow standard specifications (such as OAM) when deploying applications on the same type of platform, it is difficult for us to 100% compatible conversion Rancher has deployed The application becomes the Kato application model. Therefore, we still recommend that users directly use the source code and image-based rapid redeployment applications provided by Kato (compared to manual intervention and optimization after partial conversion, it saves time). At the same time, it is also convenient for users to understand the mechanism and process of Kato application management in this process.

Can the applications deployed by Kato be managed from the Rancher view

The resources deployed by Kato to the Kubernetes cluster are created, upgraded and recycled by the Kato controller, using the resource creation specifications defined by Kato. We do not recommend that users modify these resources directly in Rancher. However, observations can be made, such as log observations, resource monitoring observations, and so on.

Will Kato and Rancher compete in the same direction?

There is a certain crossover between the two products in terms of function, but each has its own focus. Especially on the open source route, we will definitely avoid repetitive wheel building, and at the same time, combine the excellent solutions of the community as much as possible to provide users with a complete value experience.