Fine-tune Qserv deployment

Prerequisites

For all setups

  • Access to a Kubernetes v1.19+ cluster via a valid KUBECONFIG file.

  • Dynamic volume provisionning need to be available on the Kubernetes cluster (for example kind for or GKE).

  • cert-manager

For a development workstation

  • Ubuntu LTS is recommended

  • 8 cores, 16 GB RAM, 30GB for the partition hosting docker entities (images, volumes, containers, etc). Use df command as below to find its size.

    sudo df –sh /var/lib/docker # or /var/snap/docker/common/var-lib-docker/
    
  • Internet access without proxy

  • sudo access

  • Install dependencies below:

    sudo apt-get install curl docker.io git vim
    
  • Add current user to docker group and restart gnome session

    sudo usermod -a -G docker <USER>
    
  • Install Kubernetes locally using this simple k8s install script, based on kind.

Deploy qserv-operator

qserv-operator can be deployed at cluster-scope, and will then manage all Qserv instances of the k8s cluster. It can also be deployed at namespace-scope, and will then manage Qserv instances based in the same namespace. Installing in the same k8s cluster, a qserv-operator at cluster-scope and an other at namespace-scope is not supported.

Note

If target k8s cluster does not support dynamic storage provisionning then PersistentVolumes and PersistentVolumeClaims must be manually created before installing Qserv. This project Skateful <https://github.com/k8s-school/skateful explains how to create them.

At cluster-scope

The operator will manage all Qserv instances across the cluster.

# Deploy qserv-operator at cluster-scope in "qserv-operator-system" namespace
RELEASE="2022.9.1-rc1"
kubectl apply -f https://raw.githubusercontent.com/lsst/qserv-operator/$RELEASE/manifests/operator.yaml

At namespace-scope

The operator will only manage Qserv instances in the namespace where it is installed. This setup allows running multiple instances of qserv-operator across a same Kubernetes cluster. However, Qserv CustomResourceDefinitions (CRDs) are cluster-scoped, so a conflict might occurs between two operator versions if their CRDs are not the same.

Warning

This setup is not compatible with a cluster-scope qserv-operator running in the same cluster.

# Deploy qserv-operator at namespace-scope in "qserv-dev" namespace
RELEASE="2022.9.1-rc1"
NAMESPACE="qserv-dev"
curl https://raw.githubusercontent.com/lsst/qserv-operator/$RELEASE/manifests/operator-ns-scoped.yaml | sed "s/<NAMESPACE>/$NAMESPACE/" | kubectl apply -f -

Deploy a qserv instance

with default settings

Default settings below are recommended for development purpose, or continuous integration.

# Install a qserv instance with default settings inside a given namespace
kubectl apply -k https://github.com/lsst/qserv-operator/manifests/base?ref=$RELEASE --namespace='<NAMESPACE>'

# For example, at in2p3, use urls:
# - https://github.com/lsst/qserv-operator/manifests/in2p3?ref=$RELEASE
# - https://github.com/lsst/qserv-operator/manifests/in2p3-dev?ref=$RELEASE

with custom settings

For production setup, Qserv install customization is handled with Kustomize, which is a template engine allowing to customize kubernetes Yaml files. Kustomize is integrated with kubectl (-k option).

This setup is recommended for production platforms.

Example are available, see below:

# Install a qserv instance with custom settings
kubectl apply -k https://github.com/lsst/qserv-operator/manifests/in2p3?ref=$RELEASE --namespace='qserv-prod'

In order to create a customized Qserv instance, create a Kustomize overlay using instructions below:

RELEASE="2022.9.1-rc1"
git clone --depth 1 --single-branch -b "$RELEASE" https://github.com/lsst/qserv-operator
cd qserv-operator
cp -r manifests/base/ manifests/<customized-overlay>

Then add custom setting, by editing manifests/<customized-overlay>/qserv.yaml:

And finally create customized Qserv instance:

kubectl apply -k manifests/<customized-overlay>/ --namespace='<namespace>'

Run Qserv integration tests

cd "$WORKDIR"
RELEASE="2022.9.1-rc1"
git clone --depth 1 --single-branch -b "$RELEASE" https://github.com/lsst/qserv-operator
cd qserv-operator
./tests/tools/wait-qserv-ready.sh
./tests/e2e/integration.sh

Undeploy a Qserv instance

First list all Qserv instances running in a given namespace

kubectl get qserv -n "<namespace>"

It will output something like:

NAME    CZARS   INGEST-DB   REPL-CTL   REPL-DB   WORKERS   XROOTD   AGE
qserv   1/1     1/1         1/1        1/1       2/2       2/2      2d10h

Then delete this Qserv instance

kubectl delete qserv qserv -n "<namespace>"

To delete all Qserv instances inside a namespace:

kubectl delete qserv --all -n "<namespace>"

Qserv storage will remain untouch by this operation, and a restarting Qserv instance will use the existing storage. To remove the existing Qserv storage and re-initialize Qserv databases from scratch, run:

# Delete all qserv persistent volume claims in current namespace
kubectl delete pvc -l app.kubernetes.io/managed-by=qserv-operator