# K3s

This guide assumes 3 nodes which are already setup with a minimal OS installation and network connectivity. Also make
sure DNS entries are in place for all nodes.

Our examples bellow use the following nodes:

| Node | Role | FQDN | IP Address ^ |
|---|---|---|---|
| proxy | HAProxy loadbalancer | proxy.k3s.siempie.internal | 192.168.10.230 |
| node01 | Master + Worker | node01.k3s.siempie.internal | 192.168.10.231 |
| node02 | Master + Worker | node02.k3s.siempie.internal | 192.168.10.232 |
| node03 | Master + Worker | node03.k3s.siempie.internal | 192.168.10.233 |

Our API and HTTP workloads will be proxied via the HAProxy loadbalancer. The k3s api server will be accessible at
`https://workload.k3s.siempie.internal:6443`.
[The HAProxy configuration is found here](<https://docs.simoncor.net/linux/haproxy>).

## Boostrap k3s with a custom TLS SAN

```bash
# Node 1 (first master)
curl -sfL https://get.k3s.io | sh -s - server \
  --cluster-init \
  --tls-san workload.k3s.siempie.internal \
  --tls-san node01 \
  --tls-san node01.k3s.siempie.internal

# Save token for other nodes
cat /var/lib/rancher/k3s/server/node-token
```

## Join other masters

```bash
# Node 2 and 3 (other masters)
curl -sfL https://get.k3s.io | sh -s - server \
  --server https://node01:6443 \
  --token <token-from-node01> \
  --tls-san workload.k3s.siempie.internal \
  --tls-san node02 \
  --tls-san node02.k3s.siempie.internal
```