Para rodar a aplicação:
kubectl create -f https://tonanuvem.github.io/k8s-clientes-nginx-mongodb/cliente-svc-deploy.yaml
Os seguintes serviços serão criados:
> ~/k8s-nginx-clientes-mongodb$ kubectl get svc
| NAME | TYPE | CLUSTER-IP | EXTERNAL-IP | PORT(S) | AGE |
|---|---|---|---|---|---|
| backend | ClusterIP | 10.106.72.158 | 5000/TCP | 2m40s | |
| frontend | NodePort | 10.99.142.117 | 80:32000/TCP | 2m40s | |
| mongo | ClusterIP | 10.102.58.27 | 27017/TCP | 2m40s | |
| mongoexpress | NodePort | 10.100.3.61 | 8081:32081/TCP | 2m40s |
Código fonte da aplicação: https://github.com/tonanuvem/nginx-clientes-microservice-mongodb
- Portworks
Instalar:
lsblk
VER=$(kubectl version --short | awk -Fv '/Server Version: /{print $3}')
curl -L -s -o px-spec.yaml "https://install.portworx.com/2.6?mc=false&kbver=${VER}&b=true&s=%2Fdev%2Fxvdb&c=px-fiap&stork=true&st=k8s"
kubectl apply -f px-spec.yaml
- c=px-fiap specifies the cluster name
- b=true specifies to use internal etcd
- kbVer=${VER} specifies the Kubernetes version
- s=/dev/xvdb specifies the block device to use
watch kubectl get pods -o wide -n kube-system -l name=portworx
Aguadar até: Ready 1/1 (Demora uns 4 min) --> Para sair, CTRL + C
PX_POD=$(kubectl get pods -l name=portworx -n kube-system -o jsonpath='{.items[0].metadata.name}')
kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl status
kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume list
- Agora temos um cluster Portworx de 3 nós ativado!
- Todos os 3 nós estão online e usam nomes de nós Kubernetes como os IDs de nós Portworx.
- Observe que Portworx agrupou o dispositivo de bloco de cada nó em um cluster de armazenamento de 3X o tamanho.
- O Portworx detectou o tipo de mídia do dispositivo de bloco como SSD e criou um pool de armazenamento para isso.
kubectl -n kube-system describe pods $PX_POD
Events:
| Type | Reason | Age | From | Message |
|---|---|---|---|---|
| Normal | Scheduled | 7m57s | default-scheduler | Successfully assigned kube-system/portworx-qxtw4 to k8s-node-2 |
| ... | ||||
| Warning | Unhealthy | 5m15s (x15 over 7m35s) | kubelet, k8s-node-2 | Readiness probe failed: HTTP probe failed with statuscode: 503 |
| Normal | NodeStartSuccess | 5m7s | portworx, k8s-node-2 | PX is ready on this node |
- Persistent Volume Claim (PVC) e Storage Class (SC)
Exemplo de uso: https://docs.portworx.com/portworx-install-with-kubernetes/storage-operations/create-pvcs/dynamic-provisioning/
kubectl create -f https://tonanuvem.github.io/k8s-clientes-nginx-mongodb/vol_pvc-storageclass.yaml
kubectl describe pvc mongo-pvc
Successfully provisioned volume pvc-0ebc5d99-0d7a-41d9-a218-6d02e9056e38 using kubernetes.io/portworx-volume
kubectl get pv
Verificar o volume criado dinamicamente.
Executar CLIENTE_MONGO:
kubectl create -f https://tonanuvem.github.io/k8s-clientes-nginx-mongodb/vol_mongo.yaml
kubectl create -f https://tonanuvem.github.io/k8s-clientes-nginx-mongodb/vol_clientes.yaml
kubectl get svc
./ip
Acessar : http://IP:32000
- MongoDB (https://portworx.com/run-ha-mongodb-gke/)
Criar o Deploy e SVC
POD=$(kubectl get pods | grep 'mongo-' | awk '{print $1}')
echo $POD
kubectl exec -it $POD -- mongo --host localhost
db.ships.insert({name:'USS Enterprise-D',operator:'Starfleet',type:'Explorer',class:'Galaxy',crew:750,codes:[10,11,12]})
db.ships.insert({name:'Narada',operator:'Romulan Star Empire',type:'Warbird',class:'Warbird',crew:65,codes:[251,251,220]})
db.ships.find().pretty()
db.ships.find({}, {name:true, _id:false})
db.ships.findOne({'name':'USS Enterprise-D'})
exit
NODE=$(kubectl get pods -l app=mongo -o wide | grep -v NAME | awk '{print $7}')
POD=$(kubectl get pods -l app=mongo -o wide | grep -v NAME | awk '{print $1}')
kubectl cordon $NODE && kubectl delete pod $POD && kubectl get pod -o wide && kubectl uncordon $NODE
watch kubectl get pods -l app=mongo -o wide
Verificar os dados:
POD=$(kubectl get pods | grep mongo- | awk '{print $1}')
kubectl exec -it $POD -- mongo --host localhost
db.ships.find().pretty()
db.ships.find({}, {name:true, _id:false})
db.ships.findOne({'name':'USS Enterprise-D'})
exit
- Verificar o volume
You can run pxctl commands to inspect your volume:
VOL=$(kubectl get pvc | grep mongo-pvc | awk '{print $3}')
echo $VOL
PX_POD=$(kubectl get pods -l name=portworx -n kube-system -o jsonpath='{.items[0].metadata.name}')
kubectl exec -it
$PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume inspect $ {VOL}
Retornar o node do Cluster:
kubectl uncordon ${NODE}
- Expandindo volumes:
kubectl get pvc mongo-pvc
Expanda o volume: como adicionamos o atributo allowVolumeExpansion: true à nossa classe de armazenamento, você pode expandir o PVC editando o arquivo px-mongo-pvc.yaml e, em seguida, reaplicando esse arquivo usando kubectl.
sed -i 's/10Gi/20Gi/g' px-mongo-pvc.yaml
kubectl apply -f px-mongo-pvc.yaml
Inspecione o volume e verifique se ele agora tem capacidade de 20Gi:
kubectl get pvc px-mongo-pvc
Volume agora está expandido e nosso banco de dados MongoDB não precisou ser reiniciado.
kubectl get pods
- Snapshot de um Volume:
kubectl create -f https://tonanuvem.github.io/k8s-clientes-nginx-mongodb/vol_snapshot.yaml
Snapshots comandos:
kubectl get volumesnapshot,volumesnapshotdatas
Do something stupid:
POD=
kubectl get pods | grep 'px-mongo-' | awk '{print $1}'
kubectl exec -it $POD -- mongo --host px-mongo-mongodb
db.ships.remove({})
db.ships.find({}, {name:true, _id:false})
exit
- Restore the snapshot and see your data is still there
Snapshots são como volumes, portanto, podemos prosseguir e usá-los para iniciar uma nova instância do MongoDB. Observe aqui que estamos deixando a instância antiga para continuar com sua versão do volume e estamos criando uma nova instância do MongoDB com os dados do instantâneo!
helm install --name px-mongo-snap-clone --set persistence.existingClaim=px-mongo-snap-clone stable/mongodb
- Verify data is still available. Run the client and in a shell.
POD=
kubectl get pods | grep 'px-mongo-snap' | awk '{print $1}'
kubectl exec -it $POD -- mongo --host px-mongo-snap-clone-mongodb
db.ships.findOne()
- Mongo Replicas (link: https://docs.mongodb.com/manual/replication/)
MongoDB can run in a single node configuration as we showed and in a clustered configuration using replica sets (not to be confused with the Kubernetes Stateful Sets). A replica set is a group of MongoDB instances that maintain the same data set. A replica set contains several data bearing nodes and optionally one arbiter node. Of the data bearing nodes, one and only one member is deemed the primary node, while the other nodes are deemed secondary nodes.
- Deploying a MongoDB Replica Set with Kubernetes Stateful Set
Portworx supports Stateful Sets which allow you to deploy a MongoDB replica. With stateful sets the PVC are dynamically created based on a provided storage class. Try the following command to launch a 3 node MongoDB replicas:
helm install --name px --set persistentVolume.storageClass=px-ha-sc stable/mongodb-replicaset
You can watch the 3 pods (px-mongodb-replicaset-0, px-mongodb-replicaset-1, px-mongodb-replicaset-2) start up and initialize one by one:
watch kubectl get pods -o wide
Get the volume list from pxctl, you should see 3 new 10GB volumes that were created:
kubectl exec -it $PX_POD -n kube-system -- /opt/pwx/bin/pxctl volume list
Check the health of all three cluster members using the following command:
for i in 0 1 2; do kubectl exec px-mongodb-replicaset-$i -- sh -c 'mongo --eval="printjson(db.serverStatus())"'; done
That's a lot of JSON but if you look closely you will see that px-mongodb-replicaset-0 should be your elected primary. You can connect to it and write/read data:
kubectl exec -it px-mongodb-replicaset-0 -- mongo --host px-mongodb-replicaset-0
You can learn more about what you can do with this helm chart here, feel free to keep using this shell to try out some of the commands listed:
Link: https://github.com/bitnami/charts/tree/master/bitnami/mongodb
- Helm
helm install --name mongodb --set auth.enabled=false,service.portName=mongo,persistence.existingClaim=px-mongo-pvc bitnami/mongodb