The basics : Part 1 – NDB Topology

Nutanix Database Service (NDB) revolutionizes database administration by automating and streamlining tasks, introducing one-click simplicity and seamlessly managing database provisioning and life-cycle management in a Hybrid Cloud Environment.

A wide range of functionalities provided in NDB makes the database administrator’s life easy.

Before we dive into the NDB’s Database management capabilities, let us understand a little bit about NDB Service topology.

Understanding NDB Service topology

To begin, let’s explore the various deployment options offered by NDB.

Single VM Deployment

• In this setup, only one virtual machine hosts the NDB Infrastructure services.

Scale-Out Deployment (High Available)

• In this configuration, NDB Services are distributed across multiple virtual machines to achieve load balancing and ensure high availability.

All right. Now let’s understand the PE cluster management capabilities via NDB and see if there is any relation with the NDB deployment type we discussed

NDB can have”Single” or “Multiple” Clusters. We need to enable the “Multi-Cluster” feature before we add additional clusters to the NDB

• Enabling the “Multi-Cluster” feature deploys an additional NDB Agent VM for each cluster managed via NDB.

• The Agent VM serves as a mediator for NDB, facilitating cluster-related tasks.

Now, let’s merge Deployment types with Cluster management capabilities to explore the various combinations of NDB deployments, understand their rationale, and determine the appropriate scenarios for their application.

Feeling overwhelmed? Not to worry, each combination offers unique advantages, which we’ll discuss in detail. Now, let’s delve into each type.

But hold on a moment!

Before we proceed, let’s familiarize ourselves with the following Failure domains, as we’ll reference them extensively in our discussions:

• Service Level
• VM Level
• Host Level
• Cluster Level

All set? Let’s dive in!”

Single NDB VM Managing One PE Cluster

• If all your databases reside within a single cluster and you require NDB to manage them, this deployment option is suitable.

Fault / Failure Domain

• In this scenario, the NDB VM becomes a potential single point of failure. If a failure occurs at the Service / NDB VM / Node / Cluster level, all NDB operations will be affected until the services are restored.

Single NDB VM Managing Multiple PE Cluster

• If databases are spread across multiple clusters and you require NDB to manage them, this deployment option is suitable.

• After enabling the “Multi Cluster” feature in NDB, an Agent VM will be deployed for each cluster managed by NDB.

Fault / Failure Domain

• In this scenario, the NDB VM becomes a potential single point of failure. If a failure occurs at the Service / NDB VM / Node / Cluster level, all NDB operations will be affected until the services are restored.”

Scaleout deployment / HA Enabled – Managing Single PE Cluster (NDB VMs running on single PE cluster)

• If all your databases are located within a single cluster and you require NDB to manage them with control plane high availability, this deployment option is suitable.

• Before enabling the HA feature, you must first activate the “Multi Cluster” feature in NDB.

• Enabling the “Multi Cluster” feature deploys an Agent VM.

• Additionally, enabling the HA feature installs an additional 7 VMs on the cluster.

Fault / Failure Domain

• In this scenario, NDB should be able to tolerate failures at the Service / NDB VM / Node level.

Note: Currently, the Agent VM does not have high availability. Therefore, if the Agent VM goes down, all operations towards the associated cluster will be impacted.”

Scaleout deployment / HA Enabled Managing Multiple Cluster (NDB VMs running on single PE cluster)

• If databases are distributed across multiple clusters and you require NDB to manage them with control plane high availability, this deployment option is suitable.

• Before enabling the HA feature, you must first activate the “Multi Cluster” feature in NDB.

• Enabling the “Multi Cluster” feature deploys an Agent VM.

• Additionally, enabling the HA feature installs an additional 7 VMs on the cluster.

Fault / Failure Domain

• In this scenario, NDB should be able to tolerate Service / NDB VM / Node level failures

Note: Currently, the Agent VM does not have high availability. Therefore, if the Agent VM goes down, all operations towards the cluster associated with it will be impacted.

Scaleout deployment / HA Enabled Managing Multiple Cluster (NDB VMs distributed across multiple PE cluster)

• If databases are distributed across multiple clusters and you require NDB to manage them with control plane high availability that can tolerate a PE Cluster failure, this deployment option is suitable.

• Before enabling the HA feature, you must first activate the “Multi Cluster” feature in NDB.

• Enabling the “Multi Cluster” feature deploys an Agent VM.

• Additionally, enabling the HA feature installs an additional 7 VMs on the cluster.

Fault / Failure Domain

• In this scenario, NDB should be able to tolerate failures at the Service / NDB VM / Node / Cluster level.

Note: Currently, the Agent VM does not have high availability. Therefore, if the Agent VM goes down, all operations towards the cluster associated with it will be impacted.

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Whew! I know it’s a lot of theory to absorb, but understanding the basics is crucial before setting up an NDB cluster.

We’ve covered a lot in this article, but there’s still more ground to explore. In the next installment, we’ll dive into NDB Sizing & Installation methods, providing practical insights to help you effectively configure and deploy NDB in your environment.

Stay tuned for more valuable information to enhance your understanding and mastery of Nutanix Database Service (NDB)!