Bootstrap a Talos Linux cluster for Cozystack using talos-bootstrap

talos-bootstrap is an interactive script for bootstrapping Kubernetes clusters on Talos OS.

It was created by Ænix to simplify the installation of Talos Linux on bare metal nodes in a user-friendly manner.

1. Install Dependencies

Install the following dependencies

• talosctl
• dialog
• nmap

Download the latest version of talos-bootstrap from the releases page or directly from the trunk:

curl -fsSL -o /usr/local/bin/talos-bootstrap \
    https://github.com/cozystack/talos-bootstrap/raw/master/talos-bootstrap
chmod +x /usr/local/bin/talos-bootstrap
talos-bootstrap --help

2. Prepare Configuration Files

1. Start by making a configuration directory for the new cluster:

   mkdir -p cluster1
   cd cluster1
   

2. Make a configuration patch file patch.yaml with common node settings, using the following example:

   machine:
     kubelet:
       nodeIP:
         validSubnets:
         - 192.168.100.0/24
       extraConfig:
         maxPods: 512
     kernel:
       modules:
       - name: openvswitch
       - name: drbd
         parameters:
           - usermode_helper=disabled
       - name: zfs
       - name: spl
       - name: vfio_pci
       - name: vfio_iommu_type1
     install:
       image: ghcr.io/cozystack/cozystack/talos:v1.9.5
     registries:
       mirrors:
         docker.io:
           endpoints:
           - https://mirror.gcr.io
     files:
     - content: |
         [plugins]
           [plugins."io.containerd.grpc.v1.cri"]
             device_ownership_from_security_context = true
           [plugins."io.containerd.cri.v1.runtime"]
             device_ownership_from_security_context = true      
       path: /etc/cri/conf.d/20-customization.part
       op: create
   
   cluster:
     network:
       cni:
         name: none
       dnsDomain: cozy.local
       podSubnets:
       - 10.244.0.0/16
       serviceSubnets:
       - 10.96.0.0/16
   

3. Make another configuration patch file patch-controlplane.yaml with settings exclusive to control plane nodes:

   machine:
     nodeLabels:
       node.kubernetes.io/exclude-from-external-load-balancers:
         $patch: delete
   cluster:
     allowSchedulingOnControlPlanes: true
     controllerManager:
       extraArgs:
         bind-address: 0.0.0.0
     scheduler:
       extraArgs:
         bind-address: 0.0.0.0
     apiServer:
       certSANs:
       - 127.0.0.1
     proxy:
       disabled: true
     discovery:
       enabled: false
     etcd:
       advertisedSubnets:
       - 192.168.100.0/24
   

4. To configure Keycloak as an OIDC provider, add the following section to patch-controlplane.yaml, replacing example.com with your domain:

   cluster:
     apiServer:
       extraArgs:
       oidc-issuer-url: "https://keycloak.example.com/realms/cozy"
       oidc-client-id: "kubernetes"
       oidc-username-claim: "preferred_username"
       oidc-groups-claim: "groups"
   

3. Bootstrap and Access the Cluster

Once you have the configuration files ready, run talos-bootstrap on each node of a cluster:

# in the cluster config directory
talos-bootstrap install

talos-bootstrap install -n 1.2.3.4

Repeat this step for the other nodes in a cluster.

After completing the install command, talos-bootstrap saves the cluster’s config as ./kubeconfig. Export the KUBECONFIG variable to use it:

export KUBECONFIG=$PWD/kubeconfig

Check that the cluster is available with this new kubeconfig:

kubectl get ns

Example output:

NAME              STATUS   AGE
default           Active   7m56s
kube-node-lease   Active   7m56s
kube-public       Active   7m56s
kube-system       Active   7m56s

Now you have a Kubernetes cluster prepared for installing Cozystack. To complete the installation, follow the deployment guide, starting with the Install Cozystack section.