Deployment of Mongo using ReplicaSet

Deployments where MongoDB is used in ReplicaSet mode is usually needed for

high availability and redundancy
isolating the read and write pipes for heavier workloads
backups are less disturbing for the whole solution when using replica-set setup, as all the read queries are being taken from the secondary node, while the primary node is spared to serve client requests.

Considerations

To deploy MongoDB in HA mode for Expertflow CX , please consider below given points.

MongoDB in HA should be deployed when using multi-node cluster, with replica members spread across different nodes. If one of the node goes down, the other node will take over and solution will survive
Current implement of the Expertflow MongoDB HA can be run on a single node ( not recommended )
MongoDB requires hardware specs given below

Entity	Spec
Number of replicas	2 ( 1 primary and 1 secondary )
RAM	4 GB per replica
CPU Cores	1 CPU Core per replica

Default replicaset name is “expertflow” when using MongoDB HA

Deployment

Deploy the MongoDB in HA using replica-set, follow these steps

clone the values file for the MongoDB helm chart

CODE

helm show values expertflow/mongodb-ha > helm-values/mongo-db-ha-custom-values.yaml

Edit/update values required in helm-values/mongo-db-ha-custom-values.yaml for-example, the default password under the auth section

CODE

auth:
  rootPassword: "Expertflow123"

Deploy MongoDB by running the following command.

CODE

helm upgrade --install=true --namespace=ef-external --values=helm-values/mongo-db-ha-custom-values.yaml mongo expertflow/mongodb

Check the MongoDB deployment status by running the following command:

CODE

kubectl -n ef-external rollout status sts mongo-mongodb

sample output

CODE

# kubectl -n ef-external get pods
NAME                   READY   STATUS    RESTARTS   AGE
mongo-mongodb-0        1/1     Running   0          8m10s
mongo-mongodb-1        1/1     Running   0          6m42s
mongo-mongodb-client   1/1     Running   0          5s