Better name for the repo

.github/workflows/frontend.yaml

@@ -54,7 +54,7 @@ jobs:
 
       - name: Push to ECR
         env:
-          REPOSITORY: ${{ secrets.AWS_ACCOUNT_ID }}.dkr.ecr.${{ env.AWS_REGION }}.amazonaws.com/learning-frontend
+          REPOSITORY: ${{ secrets.AWS_ACCOUNT_ID }}.dkr.ecr.${{ env.AWS_REGION }}.amazonaws.com/experiments-frontend
           IMAGE_TAG: v${{ github.sha }}
         run: |
           docker load --input /tmp/frontend_image.tar

README.md

@@ -1,10 +1,14 @@
-## Learning and sharing random stuff
+## Experiments and random stuff
 
-This repo contains step-by-step creationg of low-level Terraform + K8s + other stuff for learning purposes.
+This repo contains some notes about setting up K8s, ingresses and apps in a non-conventional way.
+
+For example:
+- Using K8s on EC2 without EKS
+- Using a raw Nginx config without using K8s ingress.
 
 ### Day 1: Set up Terraform with a remote backend
 
-Commit: https://github.com/lucabrunox/learning/tree/cd8378154c378
+Commit: https://github.com/lucabrunox/experiments/tree/cd8378154c378
 
 Define the AWS region that will be used for all the commands:
 
@@ -15,7 +19,7 @@ export AWS_REGION=eu-west-1
 Create an S3 bucket for terraform state:
 
 ```bash
-aws s3api create-bucket --acl private --bucket learning-12345-terraform --create-bucket-configuration LocationConstraint=$AWS_REGION
+aws s3api create-bucket --acl private --bucket experiments-12345-terraform --create-bucket-configuration LocationConstraint=$AWS_REGION
 ```
 
 Initialize:
@@ -24,8 +28,8 @@ Initialize:
 cd tf
 
 cat <<EOF > backend.conf
-bucket = "learning-12345-terraform"
-key    = "learning/terraform.tfstate"
+bucket = "experiments-12345-terraform"
+key    = "experiments/terraform.tfstate"
 region = "$AWS_REGION"
 EOF
 
@@ -46,17 +50,12 @@ Use asg_desired_capacity=0 to tear down the cluster.
 
 ### Day 2: Kubernetes single-node cluster on EC2 with kubeadm
 
-Commit: https://github.com/lucabrunox/learning/tree/9cc3ac81d7f
+Commit: https://github.com/lucabrunox/experiments/tree/9cc3ac81d7f
 
-Using a raw K8s instead of EKS to learn some low-level details. Some interesting facts:
+Using a raw K8s on EC2 instead of EKS, using Flannel instead of AWS CNI. Some interesting facts:
 
 - It takes 2 minutes and 20 second until all containers are in Running state.
 - A t4g.medium is needed to run a cluster. Using a t4g.nano with swap is not enough because the apiserver/etcd will keep timing out.
-- CoreDNS and kube-proxy addons are installed by default.
-- The advertising IP is coming from `ip route` and it coincides with the private IP of the instance rather than the public one.
-- Explanations of K8s networking:
-  - https://mvallim.github.io/kubernetes-under-the-hood/documentation/kube-flannel.html
-  - https://www.redhat.com/sysadmin/kubernetes-pods-communicate-nodes
 
 SSH into the EC2 instance and run crictl and kubectl commands to inspect the cluster:
 
@@ -69,49 +68,40 @@ export KUBECONFIG=/etc/kubernetes/admin.conf
 kubectl get all -A
 ```
 
-If the cluster is not up check the instance init logs:
+To check init logs:
 
 ```bash
 sudo cat /var/log/cloud-init-output.log
 ```
 
-### Day 3: A Django frontend with GH action to build a Docker image and push to ECR
+### Day 3: Sample app with Docker pushed to ECR
 
-Commit: https://github.com/lucabrunox/learning/tree/5216dfe5efd6
+Commit: https://github.com/lucabrunox/experiments/tree/5216dfe5efd6
 
 Set up following https://docs.djangoproject.com/en/5.1/intro/tutorial01/ with `django-admin startproject mysite`.
 
-The Dockerfile is self-explanatory. To try it out:
+The Dockerfile is self-explanatory:
 
 ```bash
 docker run -p 8000:8000 --rm -it $(docker build -q .)
 ```
 
-Then open http://localhost:8000
-
-To test GH actions I've set up act to run in a Docker, so that it doesn't need to be installed:
+To test GH actions I've set up act to run in a Docker, which seems to work fine:
 
 ```bash
 ./test_gh.sh
 ```
 
-Which in turn creates the frontend Docker, yay!
-
-The GH also contains a job to push to ECR, which is not tested locally.
-
-### Day 4: Deploy the Django app in K8s using the ECR image
+### Day 4: Deploy the app in K8s using the ECR image
 
-Commit: https://github.com/lucabrunox/learning/tree/5216dfe5efd6
+Commit: https://github.com/lucabrunox/experiments/tree/5216dfe5efd6
 
-Needless to say that without EKS it's more complicated, but worth the learnings.
+We're using a CronJob to get the ECR creds from the node metadata.
 
-Learnings:
-- Using CronJob to get AWS creds from the node, login to ECR, and store the secret for pulling images.
-- CronJob doesn't start immediately, need to wait a minute.
+Some notes:
 - Need to untaint control plane node in other to schedule pods.
-- Need to build the frontend image for ARM, obviously.
-- Python app fails because it can't find the UTC timezone, needs tzdata.
-- Cannot change the matching labels of a K8s deployment.
+- As we use t4g changed the GH build to ARM.
+- Python requirements also need tzdata.
 
 At the end we're able to execute the following kubectl on the EC2 instance to deploy the app and watch it working:
 
@@ -124,18 +114,16 @@ curl $(kubectl get svc frontend -o=jsonpath='{.spec.clusterIP}'):8000
 
 ### Day 5: Expose service via NLB and NodePort
 
-Commit: https://github.com/lucabrunox/learning/tree/f03d8449f869
+Commit: https://github.com/lucabrunox/experiments/tree/f03d8449f869
 
-Publicly exposing the service via NLB learnings:
-- Allowed node ports only from 30000
-- NLB security group must be configured for each listener port
-- NLBs need at least 2 subnets for redundancy
+Some notes:
+- Configured NLB with the security group in 2 subnets.
 - Django has an ALLOWED_HOSTS config to prevent Host header attacks
 - Django detects a tty when logging to stdout
 
 ```bash
 kubectl apply -f k8s/ecr-credentials.yaml
 kubectl apply -f frontend/k8s/manifest.yaml
 
-curl http://$(terraform output --raw learning_nlb_dns_name)
+curl http://$(terraform output --raw experiments_nlb_dns_name)
 ```

frontend/k8s/manifest.yaml

@@ -19,7 +19,7 @@ spec:
       containers:
         - name: frontend
           tty: true
-          image: MY_ACCOUNT.dkr.ecr.eu-west-1.amazonaws.com/learning-frontend:v29446ea079d6df7875c08c6641523f8e029caf37
+          image: MY_ACCOUNT.dkr.ecr.eu-west-1.amazonaws.com/experiments-frontend:v29446ea079d6df7875c08c6641523f8e029caf37
           imagePullPolicy: IfNotPresent
           ports:
             - containerPort: 8000