You can upgrade K3s by using the installation script, or by manually installing the binary of the desired version.

Note: When upgrading, upgrade server nodes first one at a time, then any worker nodes.

Release Channels

Upgrades performed via the installation script or using our automated upgrades feature can be tied to different release channels. The following channels are available:

Channel Description
stable (Default) Stable is recommended for production environments. These releases have been through a period of community hardening.
latest Latest is recommended for trying out the latest features. These releases have not yet been through a period of community hardening.
v1.18 (example) There is a release channel tied to each supported Kubernetes minor version. At the time of this writing, they are v1.18, v1.17, and v1.16. These channels will select the latest patch available, not necessarily a stable release.

For an exhaustive and up-to-date list of channels, you can visit the k3s channel service API. For more technical details on how channels work, you see the channelserver project.

Upgrade K3s Using the Installation Script

To upgrade K3s from an older version you can re-run the installation script using the same flags, for example:

curl -sfL https://get.k3s.io | sh -

This will upgrade to a newer version in the stable channel by default.

If you want to upgrade to a newer version in a specific channel (such as latest) you can specify the channel:

curl -sfL https://get.k3s.io | INSTALL_K3S_CHANNEL=latest sh -

If you want to upgrade to a specific version you can run the following command:

curl -sfL https://get.k3s.io | INSTALL_K3S_VERSION=vX.Y.Z-rc1 sh -

Manually Upgrade K3s Using the Binary

Or to manually upgrade K3s:

  1. Download the desired version of the K3s binary from releases
  2. Copy the downloaded binary to /usr/local/bin/k3s (or your desired location)
  3. Stop the old k3s binary
  4. Launch the new k3s binary

Restarting K3s

Restarting K3s is supported by the installation script for systemd and OpenRC.

systemd

To restart servers manually:

sudo systemctl restart k3s

To restart agents manually:

sudo systemctl restart k3s-agent

OpenRC

To restart servers manually:

sudo service k3s restart

To restart agents manually:

sudo service k3s-agent restart