How to upgrade the Talos version

Type: How-to · Audience: Cluster operator

Overview

Bump the Talos version in a tenant spec. RezusCloud detects the drift and runs a rolling upgrade (one machine at a time via the Talos API) before regenerating version-specific config.

Prerequisites

• A running tenant with at least one machine
• All machines reachable via the Talos API

Steps

1. Update the tenant spec with the new Talos version:

   curl -X PUT $SERVER/api/v1/tenants/prod \
     -H "Authorization: Bearer $TOKEN" \
     -H "Content-Type: application/json" \
     -d '{
       "metadata": {"name": "prod", "resourceVersion": 5},
       "spec": {
         "kubernetesVersion": "1.35.0",
         "talosVersion": "1.12.7",
         "controlPlaneEndpoint": "https://10.0.0.1:6443"
       }
     }'
   

2. The pre-apply upgrade hook fires automatically:

   • RezusCloud detects the version drift (spec vs observed machine versions)
   • The rolling upgrade engine upgrades one machine at a time
   • Each upgrade: Talos API upgrade → health check → rollback on failure
   • Control-plane machines are upgraded first, then workers

3. After all machines are upgraded, tofu apply runs to regenerate version-specific Talos config.

Verification

rezusctl describe cluster prod --server $SERVER

The reconciliation phase should show applied and machines should report the new talosVersion.

See also

• Components: Rolling Upgrade Engine