This is the seventh article in a series covering detailing building a Raspberry Pi Kubernetes development cluster. In the first 6 parts we have covered tting the cluster ready to run applications. In this article we will deploy Gitlab and the Gitlab Runner. We will also install PostgreSQL reduce the footprint of the Gitlab pod and make it easier to run on the cluster.
PostgreSQL
Because Gitlab will use Postgres to store it’s data we will first need to install Postgres. Lets start by creating a namespace. Create a gitlab-namespace.yaml file ina new directory with the following content
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apiVersion:v1
kind:Namespace
metadata:
name:gitlab-managed-apps
labels:
name:gitlab-managed-apps
Apply the file to the cluster
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$kubectl apply-fgitlab-namespace.yml
Next lets set up a persistent volume for Postgres using the Synology CSI driver to automatically provision a LUN on the NAS. create postgres-pvc.yml. Create these files in a subdirectory named “postgres”
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kind:PersistentVolumeClaim
apiVersion:v1
metadata:
name:postgres-pv-claim
namespace:gitlab-managed-apps
labels:
app:postgres
spec:
storageClassName:synology-iscsi-storage
accessModes:
-ReadWriteMany
resources:
requests:
storage:200Gi
We can take regular snapshots of this volume too using the automated volume snapshotter. Add the file postgres-snapshot.yml
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apiVersion:k8s.ryanorth.io/v1beta1
kind:ScheduledVolumeSnapshot
metadata:
name:postgres-scheduled-snapshot
namespace:gitlab-managed-apps
spec:
snapshotClassName:synology-snapshotclass
persistentVolumeClaimName:postgres-pv-claim
snapshotFrequency:1d
snapshotRetention:3d
snapshotLabels:
firstLabel:postgresSnapshot
Next we will add a config map to store the database connection details. postgres-configmap.yml
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apiVersion:v1
kind:ConfigMap
metadata:
name:postgres-config
namespace:gitlab-managed-apps
labels:
app:postgres
data:
POSTGRES_DB:gitlabhq_production
POSTGRES_USER:postgresadmin
POSTGRES_PASSWORD:admin123
Create a service to expose the postgres deployment. postgres-service.yml
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apiVersion:v1
kind:Service
metadata:
name:postgres
namespace:gitlab-managed-apps
labels:
app:postgres
spec:
type:ClusterIP
ports:
-port:5432
selector:
app:postgres
And finally create the deployment. postgres-deployment.yml
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apiVersion:apps/v1
kind:Deployment
metadata:
name:postgres
namespace:gitlab-managed-apps
spec:
replicas:1
selector:
matchLabels:
app:postgres
template:
metadata:
labels:
app:postgres
spec:
containers:
-name:postgres
image:postgres:latest
imagePullPolicy:"IfNotPresent"
ports:
-containerPort:5432
envFrom:
-configMapRef:
name:postgres-config
volumeMounts:
-mountPath:/var/lib/postgresql
name:postgredb
volumes:
-name:postgredb
persistentVolumeClaim:
claimName:postgres-pv-claim
-name:postgres-config
configMap:
name:postgres-config
With all the manifests in the directory postgres, you can apply them all at once like this
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$kubectl apply-fpostgres/
Gitlab
Now that we have a postgres deployment we can deploy Gitlab to the cluster. Be warned it takes quite a while for Gitlab to get up and running. Be patient.
Before we start, we are going to need a certificate that is generated by a trusted root certificate authority. If you have followed the guides so far your DNS resolution, network ingress and the cert manager deployment are all in place for this to work.
This certificate will need to be valid for 2 domains. First the domain on which Gitlab it’s self will respond and second a domain name for the container registery service.
Create a gitlab-certificate.yml file in a new gitlab directory
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apiVersion:cert-manager.io/v1
kind:Certificate
metadata:
name:gitlab-radicalgeek
namespace:gitlab-managed-apps
spec:
secretName:gitlab-radicalgeek-tls
issuerRef:
name:letsencrypt-prod
kind:ClusterIssuer
renewBefore:360h
privateKey:
rotationPolicy:Always
commonName:gitlab.radicalgeek.co.uk
dnsNames:
-gitlab.radicalgeek.co.uk
-reg.gitlab.radicalgeek.co.uk
Apply this file to the cluster, and wait for the certificate to generate
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$kubectl apply-fgitlab/gitlab-certificate.yml
$kubectl get certificates-ngitlab-managed-apps
Once the certificate is ready we can create the rest of the manifests in the gitlab directory
We will start with the persistent volume claim again. Create gitlab-storage.yml
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apiVersion:v1
kind:PersistentVolumeClaim
metadata:
name:gitlab-config
namespace:gitlab-managed-apps
spec:
accessModes:
-ReadWriteMany
resources:
requests:
storage:1Gi
storageClassName:synology-iscsi-storage
---
apiVersion:v1
kind:PersistentVolumeClaim
metadata:
name:gitlab-data
namespace:gitlab-managed-apps
spec:
accessModes:
-ReadWriteMany
resources:
requests:
storage:100Gi
storageClassName:synology-iscsi-storage
gitlab-snapshot.yml
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apiVersion:k8s.ryanorth.io/v1beta1
kind:ScheduledVolumeSnapshot
metadata:
name:gitlab-scheduled-snapshot
namespace:gitlab-managed-apps
spec:
snapshotClassName:synology-snapshotclass
persistentVolumeClaimName:gitlab-data
snapshotFrequency:1d
snapshotRetention:3d
snapshotLabels:
firstLabel:gitlabSnapshot
Next create the gitlab-deployment.yml file (note the use of the arm56 image)
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apiVersion:apps/v1
kind:Deployment
metadata:
namespace:gitlab-managed-apps
name:gitlab
labels:
app:gitlab
spec:
replicas:1
revisionHistoryLimit:1
selector:
matchLabels:
app:gitlab
template:
metadata:
labels:
app:gitlab
spec:
containers:
-name:gitlab
image:yrzr/gitlab-ce-arm64v8
imagePullPolicy:IfNotPresent
volumeMounts:
-name:config-volume
mountPath:/etc/gitlab
-name:gitlab-configmap-volume
mountPath:/etc/gitlab/gitlab.rb
subPath:gitlab.rb
-name:data-volume
mountPath:/var/opt/gitlab
ports:
-name:http-web
containerPort:80
-name:tcp-ssh
containerPort:22
-name:http-reg
containerPort:5050
volumes:
-name:gitlab-configmap-volume
configMap:
name:gitlab-config
-name:config-volume
persistentVolumeClaim:
claimName:gitlab-config
-name:data-volume
persistentVolumeClaim:
claimName:gitlab-data
gitlab-service.yml
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apiVersion:v1
kind:Service
metadata:
name:gitlab
namespace:gitlab-managed-apps
labels:
app:gitlab
spec:
selector:
app:gitlab
ports:
-name:http-web
protocol:"TCP"
port:80
targetPort:80
-name:http-reg
protocol:"TCP"
port:5050
targetPort:5050
type:ClusterIP
---
apiVersion:v1
kind:Service
metadata:
name:gitlab-ssh
namespace:gitlab-managed-apps
labels:
app:gitlab-ssh
spec:
selector:
app:gitlab
ports:
-name:tcp-git
protocol:"TCP"
targetPort:22
port:32222
nodePort:32222
type:NodePort
Finally we need to create the configuration file. In this file be sure to use the username and password you set on your postgres deployment, and ensure you are using the same domain names you registered in your certificate.
Once the deployment goes green/ready you will still have to wait some time for Gitlab to actually become available. Once it does it will be accessible over HTTPS and publicly available. You should navigate to it right away, change the admin password and begin setting it up to your tastes.
Gitlab Runner
Now that we have Gitlab installed on the cluster, we can start to store the manifests we have created so far in source control repositories. This gives us somewhere safe to store the code that deploys the cluster. But we can also take it one step further and uses Gitlab’s built in CI/CD tooling to deploy the manifests to the cluster so that any time we commit a change to our manifests to source control, Gitlab (running on the cluster) will automatically update the cluster.
To achieve this we are going to deploy the Gitlab runner using helm, but first we need to get a few things ready. Lets start with the Helm values file. Create a file called gitlab-runner-chart-value.yml
Mark is an experienced Technical Architect, Consultant and Entrepreneur. From a C# and DevOps background, for the last 8 years he has worked with startups, FTSE 100 and government organisations to build innovative cloud orientated microservice platforms.
