Upgrade an MKE installation¶
Note
Prior to upgrading MKE, review the MKE release notes for information that may be relevant to the upgrade process.
In line with your MKE upgrade, you should plan to upgrade the Mirantis Container Runtime (MCR) instance on each cluster node to version 20.10.0 or later. Mirantis recommends that you schedule the upgrade for non-business hours to ensure minimal user impact.
Important
Do not make changes to your MKE configuration while upgrading, as doing so can cause misconfiguration.
Semantic versioning¶
MKE uses semantic versioning. While downgrades are not supported, Mirantis supports upgrades according to the following rules:
When you upgrade from one patch version to another, you can skip patch versions as no data migration takes place between patch versions.
When you upgrade between minor releases, you cannot skip releases. You can, however, upgrade from any patch version from the previous minor release to any patch version of the subsequent minor release.
When you upgrade between major releases, you cannot skip releases.
Warning
Upgrading from one MKE minor version to another minor version can result in a downgrading of MKE middleware components. For more information, refer to the component listings in the release notes of both the source and target MKE versions.
Description |
From |
To |
Supported |
---|---|---|---|
Patch upgrade |
x.y.0 |
x.y.1 |
Yes |
Skip patch version |
x.y.0 |
x.y.2 |
Yes |
Patch downgrade |
x.y.2 |
x.y.1 |
No |
Minor upgrade |
x.y.* |
x.y+1.* |
Yes |
Skip minor version |
x.y.* |
x.y+2.* |
No |
Minor downgrade |
x.y.* |
x.y-1.* |
No |
Major upgrade |
x.y.z |
x+1.0.0 |
Yes |
Major upgrade skipping minor version |
x.y.z |
x+1.y+1.z |
No |
Skip major version |
x.*.* |
x+2.*.* |
No |
Major downgrade |
x.*.* |
x-1.*.* |
No |
Automated rollbacks¶
Available as of MKE 3.7.0 MKE supports automated rollbacks. As such, if an MKE upgrade fails for any reason, the system will automatically revert to the previously running MKE version and thus ensure that the cluster remains in a usable state.
Note
Rollback will be automatically initiated in the event that any step of the upgrade process does not progress within 20 minutes.
The automated rollbacks feature is enabled by default. To opt out of the function, refer to the MKE upgrade CLI command documentation.