The project is split into different directories, each responsible for another task. For the initial setup it is mandatory to follow the instructions of each directory in the following order. Subsequent changes may only require a subset of these instructions. Though, it should be safe to run each step multiple times, they should all be indempotent.

infra

Run this setup in the infra/ directory.

Make sure config.auto.tfvars with all the needed configuration-secrets is present otherwise the module cannot be applied! The file is savely stored in the password-manager.

terraform init (1)
terraform apply (2)

1	Init the terraform modules if necessary
2	Setup infrastructure and create/update inventory.ini

The setup will take longer than just the terraform apply, since it will install some. As a rule of thumb wait ca. 5 minutes after the apply to do other work.

k3s

Run this setup in the k3s/ directory.

The k3s-setup requires a inventory.ini which is automatically created by the infra. So, make sure to apply the infra at least once, before running these playbooks.

ansible-galaxy install -r requirements.yml (1)
ansible-playbook site.yml (2)

1	Install required ansible collections to create a k3s-cluster (can be omitted in subsequent runs)
2	Install k3s and download kube-config to .kube/config

The second step will override any existing kube config, this might destroy any existing settings!

k8s

Run this setup in the k8s/ directory.

Make sure config.auto.tfvars with all the needed configuration-secrets is present otherwise the module cannot be applied! The file is savely stored in the password-manager.

terraform init (1)
terraform apply (2)

1	Init the terraform modules if necessary
2	Create services in the cluster

Enlarge / Reduce size of cluster

Increase

Simply adjust the number of agents/servers in your infra/config.auto.tfvars.
Run steps 3 & 4 of the setup again

Decrease

If you want shrink the cluster DO NOT reduce the agent-amount directly! Instead proceed as the following:

Open k9s and go to :nodes
Select the highest agent and press r to drain it
Afterward that succeeded delete it with Ctrl-d
Finally reduce the amount of agents in terraform and apply the change

Responsibilities

infra/

Creation of network for the kubernetes-cluster
- A public subnet exposed to the internet for the kubernetes-servers
- A private subnet for the kubernetes-agents
Routing between the networks
Firewall rules to block everything from the servers except of:
- ping (protocol: icmp)
- kubernetes api (Usually port 6443)
- ssh (I prefer to use a non-standard port since I want to provide a git-server on port 22)
- public services, e.g. http and https (port 80 and 443)
Creating the kubernetes-servers in the public subnet
Creating the kubernetes-agents in the private subnet
Setting up routing on all servers
Setup SSH-connections
Creating DNS-records in Hetzer Cloud

k3s/

Installing k3s
Keep the software up-to-date