Você pode configurar a topologia de implantação de seus recursos do MongoDB no Kubernetes definindo NodeAffinity e PodAffinity. NodeAffinity e PodAffinity especificam onde o Kubernetes distribui os recursos personalizados do MongoDB em seu cluster do Kubernetes.
You can implement node affinity by applying node labels to specific nodes within your Kubernetes cluster and defining labelSelector fields with corrosponding labels in your MongoDB CustomResourceDefinition. When you apply node labels and matching labelSelector values, Kubernetes only deploys a given MongoDB CustomResourceDefinition on the nodes you specify within your Kubernetes cluster. Implementing node affinity rules can be useful when deploying MongoDB resources in heterogeneous node groups, as it allows you to deploy specific resources on specific node varieties.
Similarly, you can implement Pod affinity by applying labels to Pods that are running in your cluster and aligning those label values with labelSelector values defined in your MongoDB CustomResourceDefinition. When you apply labels and matching labelSelector values, Kubernetes colocates MongoDB custom resource-managed Pods with Pods with matching labels applied. By collocating Pods, you can improve system performance and reduce latency between Pods that communicate regularly. You can also define Pod antiaffinity rules which allow you to specify Pods which should not be colocated.
For Standalone and Replica Set deployments, you can apply these affinity rules to the spec.podSpec of your MongoDB CustomResourceDefinition. For Sharded Cluster deployments, you can apply these affinity rules to the spec.configSrvPodSpec, spec.shardPodSpec, and spec.mongosPodSpec sections of your MongoDB CustomResourceDefinition.
You must deploy MongoDB resources, such as mongos, shards, and config servers in the case of a Sharded Cluster deployment, in the same namespace as the MongoDB resource. However, within that namespace, you can configure the nodeAffinity and podAffinity for mongos, shards, and config server resource types in the ShardedCluster CustomResourceDefinition.
Pré-requisitos
To configure the deployment topology for your MongoDB deployment, you must either have a MongoDB replica set deployed through the MongoDB Kubernetes Operator along with labels applied to the Kubernetes resources that will align with labelSelectors defined in the MongoDB CustomResourceDefinition or meet the following prerequisites:
Labels applied to the Kubernetes resources that will align with
labelSelectorsdefined in the MongoDB CustomResourceDefinition.
Procedimento
Atualize seu manifesto CRD do MongoDB .
Preencha as seções podTemplate.spec.affinity da sua definição de Cluster Fragmentado MongoDB como mostrado no seguinte exemplo:
1 2 apiVersion: mongodb.com/v1 3 kind: MongoDB 4 metadata: 5 name: my-sharded-cluster 6 spec: 7 shardCount: 2 8 mongodsPerShardCount: 3 9 mongosCount: 2 10 configServerCount: 3 11 version: 8.0.0 12 service: my-service 13 14 opsManager: 15 configMapRef: 16 name: my-project 17 credentials: my-credentials 18 type: ShardedCluster 19 20 persistent: true 21 configSrvPodSpec: 22 podTemplate: 23 spec: 24 affinity: 25 podAffinity: 26 requiredDuringSchedulingIgnoredDuringExecution: 27 - labelSelector: 28 matchExpressions: 29 - key: security 30 operator: In 31 values: 32 - S1 33 topologyKey: failure-domain.beta.kubernetes.io/zone 34 nodeAffinity: 35 requiredDuringSchedulingIgnoredDuringExecution: 36 nodeSelectorTerms: 37 - matchExpressions: 38 - key: kubernetes.io/e2e-az-name 39 operator: In 40 values: 41 - e2e-az1 42 - e2e-az2 43 podAntiAffinity: 44 requiredDuringSchedulingIgnoredDuringExecution: 45 - podAffinityTerm: 46 topologyKey: nodeId 47 mongosPodSpec: 48 podTemplate: 49 spec: 50 affinity: 51 podAffinity: 52 requiredDuringSchedulingIgnoredDuringExecution: 53 - labelSelector: 54 matchExpressions: 55 - key: security 56 operator: In 57 values: 58 - S1 59 topologyKey: failure-domain.beta.kubernetes.io/zone 60 nodeAffinity: 61 requiredDuringSchedulingIgnoredDuringExecution: 62 nodeSelectorTerms: 63 - matchExpressions: 64 - key: kubernetes.io/e2e-az-name 65 operator: In 66 values: 67 - e2e-az1 68 - e2e-az2 69 podAntiAffinity: 70 requiredDuringSchedulingIgnoredDuringExecution: 71 - podAffinityTerm: 72 topologyKey: nodeId 73 shardPodSpec: 74 podTemplate: 75 spec: 76 affinity: 77 podAffinity: 78 requiredDuringSchedulingIgnoredDuringExecution: 79 - labelSelector: 80 matchExpressions: 81 - key: security 82 operator: In 83 values: 84 - S1 85 topologyKey: failure-domain.beta.kubernetes.io/zone 86 nodeAffinity: 87 requiredDuringSchedulingIgnoredDuringExecution: 88 nodeSelectorTerms: 89 - matchExpressions: 90 - key: kubernetes.io/e2e-az-name 91 operator: In 92 values: 93 - e2e-az1 94 - e2e-az2 95 podAntiAffinity: 96 requiredDuringSchedulingIgnoredDuringExecution: 97 - podAffinityTerm: 98 topologyKey: nodeId 99 ...