Deploy Replica Sets in a Multi-Kubernetes Cluster
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Use this procedure to create a new replica set in a member Kubernetes cluster in a multi-Kubernetes cluster MongoDB deployment.
This procedure allows you to set different settings for the replica set resource, such as overrides for statefulSet configuration. As an alternative to using this procedure, you can use the Multi-Kubernetes-Cluster Quick Start, which creates a multi-Kubernetes cluster MongoDB deployment with default settings.
Before you begin:
Learn about multi-Kubernetes-cluster deployments.
Review the list of multi-Kubernetes-cluster services and tools.
Install the Kubernetes Operator in a multi-Kubernetes cluster MongoDB deployment. See Multi-Kubernetes-Cluster Quick Start.
Complete the prerequisites.
Deploy a MongoDBMultiCluster
Resource
You can use the following procedures in this TLS-Encrypted Connections tab:
Deploy a
MongoDBMultiCluster
resourceRenew TLS Certificates for a
MongoDBMultiCluster
resource
These procedures establish TLS-encrypted connections between MongoDB hosts in a replica set, and between client applications and MongoDB deployments.
Before you begin, you must have valid certificates for TLS encryption.
Deploy a MongoDBMultiCluster
Resource
Create the secret for the TLS certificate of your MongoDBMultiCluster
resource.
Run the kubectl
command to create a new secret that stores the
MongoDBMultiCluster
resource certificate:
kubectl --context $MDB_CENTRAL_CLUSTER_FULL_NAME \ --namespace=<metadata.namespace> \ create secret tls <prefix>-<metadata.name>-cert \ --cert=<resource-tls-cert> \ --key=<resource-tls-key>
Note
You must prefix your secrets with <prefix>-<metadata.name>
.
For example, if you call your deployment my-deployment
and you set
the prefix to mdb
, you must name the TLS secret for the
client TLS communications mdb-my-deployment-cert
. Also,
you must name the TLS secret for internal cluster authentication
(if enabled) mdb-my-deployment-clusterfile
.
Create the ConfigMap to link your CA with your MongoDBMultiCluster
resource.
Run the kubectl
command to link your CA to your MongoDBMultiCluster
resource.
Specify the CA certificate file that you must always name
ca-pem
for the MongoDBMultiCluster
resource:
kubectl --context $MDB_CENTRAL_CLUSTER_FULL_NAME \ --namespace=<metadata.namespace> \ create configmap custom-ca -from-file=ca-pem=<your-custom-ca-file>
Configure kubectl
to use the central cluster's namespace.
If you have not done so already, run the following commands to run
all kubectl
commands on the central cluster in the default
namespace.
kubectl config use-context $MDB_CENTRAL_CLUSTER_FULL_NAME kubectl config set-context $(kubectl config current-context) \ --namespace=mongodb
Copy and paste the sample resource.
Copy the sample replica set YAML file and paste it into a new text file.
Change the file's settings to match your desired replica set configuration.
1 # This example provides statefulSet overrides per cluster. 2 3 apiVersion: mongodb.com/v1 4 kind: MongoDBMultiCluster 5 metadata: 6 name: multi-replica-set 7 spec: 8 version: 4.4.0-ent 9 type: ReplicaSet 10 duplicateServiceObjects: false 11 credentials: my-credentials 12 opsManager: 13 configMapRef: 14 name: my-project 15 clusterSpecList: 16 - clusterName: cluster1.example.com 17 members: 2 18 statefulSet: 19 spec: 20 template: 21 spec: 22 containers: 23 # Example of custom sidecar containers. Remove it before using the file in production. 24 - name: sidecar1 25 image: busybox 26 command: [ "sleep" ] 27 args: [ "infinity" ] 28 # Use the following settings to override the default storage size of the "data" Persistent Volume. 29 volumeClaimTemplates: 30 - metadata: 31 name: data 32 spec: 33 resources: 34 requests: 35 storage: 1Gi 36 - clusterName: cluster2.example.com 37 members: 1 38 statefulSet: 39 spec: 40 template: 41 spec: 42 containers: 43 # Example of custom sidecar containers. Remove it before using the file in production. 44 - name: sidecar2 45 image: busybox 46 command: [ "sleep" ] 47 args: [ "infinity" ] 48 volumeClaimTemplates: 49 - metadata: 50 name: data 51 spec: 52 resources: 53 requests: 54 storage: 1Gi 55 - clusterName: cluster3.example.com 56 members: 1 57 statefulSet: 58 spec: 59 template: 60 spec: 61 containers: 62 # Example of custom sidecar containers. Remove it before using the file in production. 63 - name: sidecar3 64 image: busybox 65 command: [ "sleep" ] 66 args: [ "infinity" ] 67 volumeClaimTemplates: 68 - metadata: 69 name: data 70 spec: 71 resources: 72 requests: 73 storage: 1Gi 74 75 ...
Change the settings to your preferred values.
Key | Type | Description | Example |
---|---|---|---|
string | Label for the Resource names must be 44 characters or less. See also |
| |
string | Version of MongoDB that this The format should be IMPORTANT: Ensure that you choose a compatible MongoDB Server version. Compatible versions differ depending on the base image that the MongoDB database resource uses. To learn more about MongoDB versioning, see MongoDB Versioning in the MongoDB Manual. |
| |
string | Name of the ConfigMap with the Ops Manager connection
configuration. The
This value must exist on the same namespace as the resource you want to create. IMPORTANT: The Kubernetes Operator tracks any changes to the
ConfigMap and reconciles the state of the |
| |
spec .clusterSpecList .clusterName | string | Name of the cluster in the |
|
spec .clusterSpecList .members | integer | The number of members in this cluster. |
|
spec .clusterSpecList .statefulSet .spec | collection | Optional. Provides the configuration for the StatefulSet override for each of
the cluster's StatefulSets in a multi-Kubernetes cluster MongoDB deployment. If specified at an individual
cluster level under | See the example. |
spec .clusterSpecList .statefulSet .spec .volumeClaimTemplates .spec | collection | Optional. If specified, provides a per-cluster override for the default storage size of the volumeClaimtemplates, for the persistent volume that stores the data. | See the example. |
string | Name of the secret you created as Ops Manager API authentication credentials for the Kubernetes Operator to communicate with Ops Manager. The Ops Manager Kubernetes Secret object holding the Credentials must exist on the same Namespace as the resource you want to create. IMPORTANT: The Kubernetes Operator tracks any changes to the Secret
and reconciles the state of the |
| |
string | Type of |
|
Add any additional accepted settings for a MongoDBMultiCluster
resource deployment.
You can also add any optional settings to the object specification. See Multi-Kubernetes-Cluster Resource Specification.
Save this replica set config file with a .yaml
extension.
Start your replica set deployment.
In any directory, invoke the following Kubernetes command to create your replica set:
kubectl apply -f <replica-set-conf>.yaml
Track the status of your multi-Kubernetes cluster MongoDB deployment.
To check the status of your MongoDBMultiCluster
resource, use the following command on the central cluster:
kubectl get mdbmc <resource-name> -o yaml -w
With the -w
(watch) flag set, when the configuration changes, the output
refreshes immediately until the status phase achieves the Running
state.
To learn more about resource deployment statuses, see Troubleshoot the Kubernetes Operator.
Renew TLS Certificates for a MongoDBMultiCluster
Resource
Renew your TLS certificates periodically using the following procedure.
Renew the secret for a MongoDBMultiCluster
resource.
Run this kubectl
command to renew an existing secret that stores the certificates for the MongoDBMultiCluster
resource:
kubectl --context $MDB_CENTRAL_CLUSTER_FULL_NAME \ --namespace=<metadata.namespace> \ create secret tls <prefix>-<metadata.name>-cert \ --cert=<resource-tls-cert> \ --key=<resource-tls-key> \ --dry-run=client \ -o yaml | kubectl apply -f -
This procedure doesn't encrypt connections between MongoDB hosts in a replica set, and between client applications and MongoDB deployments.
Deploy a MongoDBMultiCluster
Resource
Configure kubectl
to use the central cluster's namespace.
If you have not done so already, run the following commands to run
all kubectl
commands on the central cluster in the default
namespace.
kubectl config use-context $MDB_CENTRAL_CLUSTER_FULL_NAME kubectl config set-context $(kubectl config current-context) \ --namespace=mongodb
Copy and paste the sample resource.
Copy the sample replica set YAML file and paste it into a new text file.
Change the file's settings to match your desired replica set configuration.
1 # This example provides statefulSet overrides per cluster. 2 3 apiVersion: mongodb.com/v1 4 kind: MongoDBMultiCluster 5 metadata: 6 name: multi-replica-set 7 spec: 8 version: 4.4.0-ent 9 type: ReplicaSet 10 duplicateServiceObjects: false 11 credentials: my-credentials 12 opsManager: 13 configMapRef: 14 name: my-project 15 clusterSpecList: 16 - clusterName: cluster1.example.com 17 members: 2 18 statefulSet: 19 spec: 20 template: 21 spec: 22 containers: 23 # Example of custom sidecar containers. Remove it before using the file in production. 24 - name: sidecar1 25 image: busybox 26 command: [ "sleep" ] 27 args: [ "infinity" ] 28 # Use the following settings to override the default storage size of the "data" Persistent Volume. 29 volumeClaimTemplates: 30 - metadata: 31 name: data 32 spec: 33 resources: 34 requests: 35 storage: 1Gi 36 - clusterName: cluster2.example.com 37 members: 1 38 statefulSet: 39 spec: 40 template: 41 spec: 42 containers: 43 # Example of custom sidecar containers. Remove it before using the file in production. 44 - name: sidecar2 45 image: busybox 46 command: [ "sleep" ] 47 args: [ "infinity" ] 48 volumeClaimTemplates: 49 - metadata: 50 name: data 51 spec: 52 resources: 53 requests: 54 storage: 1Gi 55 - clusterName: cluster3.example.com 56 members: 1 57 statefulSet: 58 spec: 59 template: 60 spec: 61 containers: 62 # Example of custom sidecar containers. Remove it before using the file in production. 63 - name: sidecar3 64 image: busybox 65 command: [ "sleep" ] 66 args: [ "infinity" ] 67 volumeClaimTemplates: 68 - metadata: 69 name: data 70 spec: 71 resources: 72 requests: 73 storage: 1Gi 74 75 ...
Change the settings to your preferred values.
Key | Type | Description | Example |
---|---|---|---|
string | Label for the Resource names must be 44 characters or less. See also |
| |
string | Version of MongoDB that this The format should be IMPORTANT: Ensure that you choose a compatible MongoDB Server version. Compatible versions differ depending on the base image that the MongoDB database resource uses. To learn more about MongoDB versioning, see MongoDB Versioning in the MongoDB Manual. |
| |
string | Name of the ConfigMap with the Ops Manager connection
configuration. The
This value must exist on the same namespace as the resource you want to create. IMPORTANT: The Kubernetes Operator tracks any changes to the
ConfigMap and reconciles the state of the |
| |
spec .clusterSpecList .clusterName | string | Name of the cluster in the |
|
spec .clusterSpecList .members | integer | The number of members in this cluster. |
|
spec .clusterSpecList .statefulSet .spec | collection | Optional. Provides the configuration for the StatefulSet override for each of
the cluster's StatefulSets in a multi-Kubernetes cluster MongoDB deployment. If specified at an individual
cluster level under | See the example. |
spec .clusterSpecList .statefulSet .spec .volumeClaimTemplates .spec | collection | Optional. If specified, provides a per-cluster override for the default storage size of the volumeClaimtemplates, for the persistent volume that stores the data. | See the example. |
string | Name of the secret you created as Ops Manager API authentication credentials for the Kubernetes Operator to communicate with Ops Manager. The Ops Manager Kubernetes Secret object holding the Credentials must exist on the same Namespace as the resource you want to create. IMPORTANT: The Kubernetes Operator tracks any changes to the Secret
and reconciles the state of the |
| |
string | Type of |
|
Add any additional accepted settings for a MongoDBMultiCluster
resource deployment.
You can also add any optional settings to the object specification. See Multi-Kubernetes-Cluster Resource Specification.
Save this replica set config file with a .yaml
extension.
Start your replica set deployment.
In any directory, invoke the following Kubernetes command to create your replica set:
kubectl apply -f <replica-set-conf>.yaml
Track the status of your multi-Kubernetes cluster MongoDB deployment.
To check the status of your MongoDBMultiCluster
resource, use the following command on the central cluster:
kubectl get mdbmc <resource-name> -o yaml -w
With the -w
(watch) flag set, when the configuration changes, the output
refreshes immediately until the status phase achieves the Running
state.
To learn more about resource deployment statuses, see Troubleshoot the Kubernetes Operator.