Before Rancher 2.3, a new version of the always Rancher released along with the new version Kubernetes, if you want to use the latest version of Kubernetes, then you need to upgrade in order to use Rancher. Rancher 2.3 changes this model - now, you can update metadata stored as available Kubernetes version, so that the upgrade process and upgrade process Rancher server cluster Kubernetes decoupling.
Kubernetes version control
About release version control in Kubernetes document has been described in detail, it is worth mentioning that the version of each Kubernetes have followed XYZ format:
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X = major version
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Y = minor version
- Z = Fix Version (patch version)
Kubernetes community roughly every three months will release a minor version (1.14> 1.15), released updated versions of these many desirable features and improvements. Despite being labeled as "minor version", but these versions are still very important!
Patch version (1.15.1-> 1.15.2) is updated more frequently and are important because they contain important security and bug fixes for the latest version of the minor. They resolved:
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Security Vulnerability
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Repair affect most users can not solve the problem
- Based on customer and product interception Kubernetes
Kubernetes officials hope will cluster "reasonably" update into the production environment, and "approximately" running the latest version of the patch. They can publish three minor releases at the same time. All this means that if your Kubernetes version behind the latest version has some patch version, then if you want to know "when is the best time to upgrade cluster", then the answer may be upgraded as soon as possible in order to ensure safe and reliable clusters. If you have a few minor version of Kubernetes later version, then the answer is before the upgrade path becomes difficult, you should upgrade now.
The Rancher efforts by implementing the "one-click upgrade" to make the process simple and easy to manage. Before Rancher 2.3, a new version of the always Rancher adaptation Kubernetes latest version of the patch. Important security fixes have been ported to the new release, so you can use the new version of the patch Kubernetes after Rancher upgrade.
K8s version and the version of decoupling Rancher
Rancher before version 2.3, the upgrade will start Rancher cluster to the latest version of Kubernetes requires two steps:
1, Rancher server upgrade
2, version upgrade Kubernetes downstream cluster
Now, everything is different. In Rancher 2.3, you can upgrade directly Kubernetes cluster to the latest version, and no need to upgrade Rancher. Because, the decoupling of the Rancher Kubernetes metadata in Rancher 2.3.
Clusters running RKE Rancher deployment, which is an open source Kubernetes Rancher's release, it allows you to run anywhere Docker. Before Rancher 2.3, start a different version of Kubernetes information stored in different places. This data and the data code library close, so any need to update a value of Rancher released a new version. Not a position that allows access to the system need to pass to the value of the cluster. Rancher 2.3 reconstruct the entire method to meet the following requirements:
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We will continue to deliver Kubernetes metadata to a compatible Rancher server
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Clearly map all metadata components to Kubernetes version
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All content can be accessed easily from Rancher API
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Availability and support path offline settings
- To enable or disable the upgrade program, set the value used in the upgrade easy to configure
Note: Kubernetes API changes between two minor versions, so minor version upgrade may not be successful. For example, in Kubernetes 1.15 in API has undergone major changes, the highest version supported in your Rancher server is Kubernetes 1.14, at this time if you want to upgrade to version 1.15 Kubernetes, then, need to be upgraded to support Rancher Kubernetes 1.15.
Rancher metadata
Rancher periodically synchronize and download metadata, these data can not be obtained directly from the UI, but the user can view in the API.
Metadata RKE configuration determines the location of the frequency synchronization and download data Rancher metadata. You can start with the UI [Setup] found under, or through the API /v3/settings/rke-metadata-configthis path get. It includes the following options:
Of course, you can also choose to manually update the operating address in the upper right corner: Tools> Drivers> Refresh Kubernetes Metadata . For offline setting, you can choose to copy the configuration to the default URL Rancher metadata repository. You can also download the file that contains the system image, just click on the lower left corner Rancher Rancher UI version to download.
It works as follows:
Rancher v2.3.0 beginning Kubernetes default choose the following versions:
Kubernetes released version 1.15.5, fixes an important CVE, and our current version 1.15.4 affected by the security breach.
Rancher test team will test the new version, so that it could be used in the Rancher. User simply by selecting Tools> Drivers> Refresh Kubernetes Metadata to update the metadata.
The latest version of Kubernetes (1.14.8,1.15.5 and 1.16.2) can now be used in the same Rancher version (v2.3.0) in.
With this change, you can schedule to ensure that the cluster-to-date, and released a new version of the Rancher Rancher server time-independent.
Rancher has always been committed to all aspects of Kubernetes are simple, and we will continue to add more features and be more optimized, we hope to receive your feedback!