To build a NetApp Clustered Data ONTAP (cDOT) lab you deploy two ONTAP Simulator OVAs on a VMware hypervisor, give each node four virtual NICs — two on a private non-routable cluster interconnect and two on your routable management network — initialize the first node with boot-menu option 4, assign it a node-management IP, create the cluster, then join the second node using a 169.254.x.x interconnect address from the first. The whole thing runs in software with no NetApp hardware, needs about 8 GB of RAM per node, and ONTAP 9.5 remains the go-to simulator version for lab and certification work.
That's the summary an AI Overview will hand you. What it can't show you is the order operations actually happen in and the two or three places labs reliably break — adapter mapping, the create-vs-join fork, and license uploads. The animated build-flow diagram, the adapter-mapping table, and the reset-and-retry playbook below are the parts you'll come back to when your cluster won't form.
If you're looking to gain hands-on experience with NetApp's storage platform, setting up a lab environment is one of the best ways to learn. In this guide, we'll walk through how to set up a test lab for NetApp Clustered Data ONTAP (CDOT)—NetApp's scale-out storage operating system.
Getting Started with NetApp CDOT
Our focus here is specifically on Cluster Mode, which has been the default deployment model since the retirement of 7-Mode. While 7-Mode was widely used in legacy environments, it was last updated in ONTAP 8.2.3, and is no longer recommended for new installations.
Important Note
If you're working in a production environment or planning for certification, be aware that ONTAP is now well into the 9.x series. However, 9.5 remains a solid version for lab testing and skills development. This guide will cover Clustered ONTAP version 9.5, which is still widely used in labs and legacy environments, even though newer versions are available.
7-Mode vs Cluster Mode: what changed
| Dimension | 7-Mode (legacy) | Cluster Mode / cDOT (current) |
|---|---|---|
| Architecture | Dual-controller HA pair | Scale-out cluster, up to 24 nodes |
| Last release | ONTAP 8.2.3 (EOL) | ONTAP 9.x, actively shipping |
| Tenancy model | Physical filer + vFilers | Storage Virtual Machines (SVMs) |
| Volume mobility | Limited | Non-disruptive volume/LIF moves |
| Namespace | Per-controller | Cluster-wide |
| Licenses | 7-Mode keys | cDOT keys — not interchangeable |
| Use this when | Only to match an existing legacy filer | Every new lab, cert, or production build |
The takeaway: unless you are specifically reproducing an old 7-Mode filer, build Cluster Mode. NetApp retired 7-Mode as a forward path, so certification tracks and current tooling all assume cDOT.
Lab Requirements and Prerequisites
Hardware and Software Requirements
- A virtualization platform: VMware ESXi (preferred for multi-node clusters), VMware Workstation, or VMware Player
- Memory requirements: Each ONTAP node requires 8 GB of RAM. For a basic two-node cluster, plan for at least 16 GB of total system memory
- NetApp NOW account: Access to the NetApp Support site (now.netapp.com) to download ONTAP OVA files, licenses, and documentation
Files to Download
- ONTAP Simulator OVA (specific to your virtualization platform—ESXi or Workstation)
- License file (must match the ONTAP version you're installing)
- Setup Guide for ONTAP 9.5 (used to supplement these instructions)
- OnCommand Unified Manager (optional but helpful for managing multiple NetApp systems)
Critical Requirement
Make sure the license file and OVA file are from the same ONTAP version. Licenses for 7-Mode will not work with Clustered ONTAP (CDOT).
Network Setup and Planning
Before deploying your ONTAP virtual appliances, you'll need to set up 2 to 3 virtual networks depending on your lab goals:
- Management Network – This network should be routable to your laptop or workstation. Used for ONTAP system manager, SSH, and general cluster management.
- CDOT Internal Network – A non-routable private network for communication between ONTAP nodes (cluster interconnect). Should only be accessible by your ONTAP virtual machines.
- NAS/Data Network (Optional) – If you plan to present NFS or CIFS shares, this network should be routable to your laptop or client machines.
IP Address Planning
Have the following information ready before deployment:
- Default Gateway and Netmask for your Management network
- DNS Server IP address
- Cluster Name
- Cluster Management IP address
- Node Management IP addresses for each node (you'll need two for a basic lab)
Installing the ONTAP Simulator OVAs
The ONTAP simulator is distributed as an OVA (Open Virtualization Appliance)—a prepackaged virtual machine image that includes the system configuration, virtual disks, and startup scripts. OVAs are widely supported across VMware platforms including ESXi, Workstation, Player, and Fusion.
Deploy the First ONTAP Node (NetApp01)
- Log in to your ESXi host or vCenter
- Launch the VM Deployment Wizard - Right-click on the ESXi host and select Create/Register VM
- Choose "Deploy a virtual machine from an OVF or OVA file"
- Upload the OVA file and give the VM a meaningful name (e.g., NetApp01)
- Configure VM settings during the wizard, including target datastore and network adapters
Network Configuration Warning
Be careful to assign the correct adapters to the correct networks. Misconfigured networking is one of the most common issues during cluster setup. Assign the four virtual network adapters as follows. This mapping is the single most important thing to get right — if the interconnect adapters land on a routable or bridged network, HA and cluster join break in ways that are painful to diagnose.
| Adapter | Maps to | ONTAP interface (typical) | Routable? | Purpose |
|---|---|---|---|---|
| Adapter 1 | cDOT private network | e0a | No (host-only/internal) | Cluster interconnect |
| Adapter 2 | cDOT private network | e0b | No (host-only/internal) | Cluster interconnect (redundant) |
| Adapter 3 | Management network | e0c | Yes | System Manager, SSH, node mgmt |
| Adapter 4 | Management or NAS/data | e0d | Yes | Data LIFs (NFS/CIFS) or mgmt |
Configuring ONTAP Simulator Nodes
Now that you've successfully deployed your ONTAP simulator OVAs, it's time to configure each virtual node. This section will guide you through the initial setup of the first node, which includes performing a clean installation, assigning network settings, and configuring the cluster.
Step 1: Initialize Node 1
- Power on the first node (NetApp01)
- Watch the boot screen carefully. When prompted, press Ctrl + C to access the Boot Menu
- Select Boot Option 4: Clean Configuration and Initialize All Disks
- You'll be asked to confirm - answer Yes to both prompts
- The system will automatically reboot once complete
Reset Tip
If you ever want to reset and start over, reboot the VM, press Ctrl + C during boot, and again choose option 4 for a fresh install.
Step 2: Management Interface and IP Configuration
After the reboot, ONTAP will ask if you want to enable AutoSupport. Since this is a lab setup, you can safely answer No. Next, ONTAP will prompt you to select a management network interface. By default, it will suggest e0c. You can simply press Enter to accept the default. You'll now be prompted to enter networking details for this node's management interface:
- Node Management IP Address
- Subnet Mask
- Default Gateway
Setting Up the Second Cluster Node
With your first node fully configured and the cluster initialized, it's time to add the second node to the cluster. This step allows you to simulate a multi-node production environment with features like high availability (HA), logical interface (LIF) failover, and distributed storage.
Joining the Existing Cluster
After the basic network configuration is complete, ONTAP will prompt you to begin the cluster setup process. When asked "Create or join a cluster?", select Join. Enter the IP address of an interface on the private cluster network from the first node (visible in System Manager under Network → Network Interfaces, typically 169.254.x.x). This tells ONTAP how to find the existing cluster and join it. The system will handle the discovery and synchronization automatically.
Applying ONTAP Licenses
- Open a web browser and go to: https://
- Log in with your admin credentials
- In the top-right corner of System Manager, click the plus icon ➕ or navigate to: Cluster → Settings → Licenses
- Click Add Licenses
- When prompted, click Choose File, then select the license file you downloaded earlier
- Click Add to apply the licenses
Troubleshooting License Uploads
If you encounter an error while uploading the license file (a common issue with the simulator), try the following:
- Open the license file in a text editor (e.g., Notepad)
- Copy only the actual license keys (each is a 28-character alphanumeric string)
- Paste them into the license entry field as a comma-separated list
ABCDEFGH1234567890WXYZ1234,ZYXWVUT9876543210LKJHGFEDCBA
When the Lab Won't Cooperate
Most first-time cDOT labs fail in one of four predictable places. Here is the symptom-to-fix map before you start second-guessing the whole build:
| Symptom | Likely cause | Fix |
|---|---|---|
| Second node never sees the cluster on Join | Interconnect adapters on the wrong (routable/bridged) network | Reassign adapters 1 and 2 to the host-only/internal private network; the join IP must be a 169.254.x.x address from node 1 |
| Node boots to a config you didn't want | Previous init left stale state | Reboot, press Ctrl + C, choose boot option 4 (Clean Configuration and Initialize All Disks), answer Yes twice |
| System Manager unreachable in browser | Management IP on a non-routable network, or wrong gateway/netmask | Confirm e0c has your node-management IP and that the management network is routable to your workstation |
| License upload throws an error | Simulator quirk feeding the raw file | Open the file, copy only the 28-character keys, paste them comma-separated; verify the license version matches the OVA version |
| Cluster forms but HA takeover fails | Only one interconnect adapter mapped | Both e0a and e0b must be on the private network for redundant interconnect |
The reset-and-retry loop (Ctrl + C → option 4) is your friend here. A lab is precisely the place to wipe a node and rebuild it in five minutes rather than debug a half-broken state.
Summary and Next Steps
Congratulations—you've successfully built a working two-node NetApp Clustered ONTAP (CDOT) lab environment. You've deployed virtual ONTAP nodes, configured a cluster, assigned management IPs, and applied the necessary license keys to unlock core features. Your environment is now ready for the next phase: creating aggregates, configuring Storage Virtual Machines (SVMs), and enabling protocols like NFS, SMB/CIFS, or iSCSI. These will allow you to simulate real-world use cases such as hosting file shares, mounting exports, and testing storage automation workflows.
Suggested Next Steps
- Log in to System Manager and explore the Cluster → Nodes, Network Interfaces, and Disks views
- Try creating an aggregate manually via the CLI or UI
- Begin planning your SVM and volume layout to match a use case you're familiar with
Learning Tip
The best way to learn ONTAP is by breaking things in a safe environment—and now you have one. Experiment freely and use the reset/redeploy process when needed.
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