ansible/README.md

# TuDatTr IaC

**I do not recommend this project being used for ones own infrastructure, as
this project is heavily attuned to my specific host/network setup**
The Ansible Project to provision fresh Debian VMs for my Proxmox instances.
Some values are hard coded such as the public key both in
[./scripts/debian_seed.sh](./scripts/debian_seed.sh) and [./group_vars/all/vars.yml](./group_vars/all/vars.yml).

## Prerequisites

- [secrets.yml](secrets.yml) in the root directory of this repository.
  Skeleton file can be found as [./secrets.yml.skeleton](./secrets.yml.skeleton).
- IP Configuration of hosts like in [./host_vars/\*](./host_vars/*)
- Setup [~/.ssh/config](~/.ssh/config) for the respective hosts used.
- Install `passlib` for your operating system. Needed to hash passwords ad-hoc.

## Improvable Variables

- `group_vars/k3s/vars.yml`:
  - `k3s.server.ips`: Take list of IPs from host_vars `k3s_server*.yml`.
  - `k3s_db_connection_string`: Embed this variable in the `k3s.db.`-directory.
    Currently causes loop.

## Run Playbook

To run a first playbook and test the setup the following command can be executed.

```sh
ansible-playbook -i production -J k3s-servers.yml
```

This will run the [./k3s-servers.yml](./k3s-servers.yml) playbook and execute
its roles.

## After successful k3s installation

To access our Kubernetes cluster from our host machine to work on it via
flux and such we need to manually copy a k3s config from one of our server nodes to our host machine.
Then we need to install `kubectl` on our host machine and optionally `kubectx` if we're already
managing other Kubernetes instances.
Then we replace the localhost address inside of the config with the IP of our load balancer.
Finally we'll need to set the KUBECONFIG variable.

```sh
mkdir ~/.kube/
scp k3s-server00:/etc/rancher/k3s/k3s.yaml ~/.kube/config
chown $USER ~/.kube/config
sed -i "s/127.0.0.1/192.168.20.22/" ~/.kube/config
export KUBECONFIG=~/.kube/config
```

Install flux and continue in the flux repository.

## Longhorn Nodes

To create longhorn nodes from existing kubernetes nodes we want to increase
their storage capacity. Since we're using VMs for our k3s nodes we can
resize the root-disk of the VMs in the proxmox GUI.

Then we have to resize the partitions inside of the VM so the root partition
uses the newly available space.
When we have LVM-based root partition we can do the following:

```sh
# Create a new partition from the free space.
sudo fdisk /dev/sda
# echo "n\n\n\n\n\nw\n"
# n > 5x\n > w > \n
# Create a LVM volume on the new partition
sudo pvcreate /dev/sda3
sudo vgextend  k3s-vg /dev/sda3
# Use the newly available storage in the root volume
sudo lvresize -l +100%FREE -r /dev/k3s-vg/root
```