8 VMware NSX Alternatives to Consider in 2025

What Is VMware NSX?

VMware NSX is a network virtualization platform for managing and automating networking services. It allows for the creation of a virtualized network above the physical infrastructure layer. NSX provides a software-defined approach to networking, enabling organizations to deploy connectivity environments that are scalable, and easily managed through centralized orchestration.

NSX can decouple network functions from the underlying hardware, making network management more application-centric. This platform includes features such as logical switching, routing, and firewall capabilities. Organizations can use it to achieve microsegmentation, improving security across their networks. NSX also integrates with existing VMware vSphere environments, supporting operations like workload mobility and global security configuration.

This is part of a series of articles about Kubernetes networking.

In this article:

• Why Consider Alternatives to VMware NSX?
• Key Features to Look for in Network Virtualization Solutions
• Notable VMware NSX Alternatives

Why Consider Alternatives to VMware NSX?

There are several reasons organizations might explore alternative network virtualization platforms to VMware NSX. These limitations were reported by users on the G2 platform:

1. Cost and licensing challenges: NSX is a premium product, and its pricing structure can make it difficult for smaller organizations to justify the investment. Recent changes in VMware’s licensing model, especially after Broadcom’s acquisition, have introduced additional costs for features such as the distributed firewall (DFW), north-south firewall, and load balancing services. These are now offered as add-ons rather than being part of the core licensing.
2. Complexity of implementation and learning curve: Deploying VMware NSX often requires significant expertise in networking and virtualization. The initial setup can be complex, with a steep learning curve even for experienced teams. Moreover, functionalities, such as API usage for configurations not accessible via the GUI, further heighten the complexity.
3. Integration challenges: While NSX integrates within VMware ecosystems, extending this integration to third-party systems or non-VMware environments can be challenging. Additional components like NSX advanced load balancer (formerly AVI Networks) and intrusion detection/prevention systems (IDS/IPS) often require separate appliances or software.
4. Support and usability issues: VMware’s customer support is generally knowledgeable, but resolution times for complex issues can be slow, which is problematic during critical outages. Additionally, the GUI has limitations compared to the API, requiring users to have API proficiency for certain troubleshooting and configurations.
5. Feature overload and lack of internal monitoring: NSX’s extensive feature set can be overwhelming. Organizations may struggle to navigate and utilize all the features effectively. Furthermore, NSX lacks built-in monitoring tools comparable to those in traditional firewalls, relying instead on external solutions for these functions.

Key Features to Look for in Network Virtualization Solutions

Organizations should consider the following capabilities when choosing a network virtualization platform.

Scalability and Performance

A network virtualization platform should accommodate growth without compromising speed or efficiency. High-performance networks ensure minimal latency and downtime. The ability to scale is vital when organizations expand operations, whether through increased user load or adding new branches.

Performance features such as load balancing and efficient resource allocation help optimize the network to handle sudden spikes in traffic and ensure equitable resource distribution among users. Solutions that provide monitoring and diagnostics tools can also be beneficial. They allow for proactive network management, identifying performance bottlenecks and addressing issues.

Integration with Existing Infrastructure

Compatibility with existing systems reduces the need for significant overhauls, saving time and money. Solutions that support diverse environments, including cloud, on-premises, and hybrid models, offer flexibility for organizations managing complex IT ecosystems.

A virtualization solution should also work with existing security, management, and operational tools to ensure a cohesive IT strategy. Interoperability with hardware and software from various vendors allows organizations to leverage existing investments, reduces redundancy, minimizes disruption during deployment, and enables smoother transitions to new networking models.

Security Capabilities

The chosen solution should have extensive security features. Network segmentation, firewalling, and intrusion detection are essential for protecting sensitive data and systems. Microsegmentation capabilities provide granular security controls, allowing for stringent access management and reducing potential attack surfaces.

The ability to integrate with broader security ecosystems, such as third-party monitoring and incident response tools, improves overall network security posture. Automated security policies and compliance reporting features also ensure that security measures align with industry standards and regulations.

Related content: Read our detailed guide to Kubernetes network security

Automation and Orchestration

Automation and orchestration simplify network management, reducing the manual workload on IT teams and minimizing human error. Automated processes, such as configuration management and deployment, improve operational efficiency by allowing quick updates and changes across the network landscape.

Orchestration tools that provide centralized network management from a single interface help unify and simplify complex network operations. These tools should offer APIs for integration with existing workflows and support automation of routine tasks.

Related content: Read our guide to container networking

Notable VMware NSX Alternatives

1. Calico

Calico offers a unified network security and observability platform to protect Kubernetes, hybrid, and multi-cloud environments. By unifying security and observability into a single solution, Calico helps organizations reduce tool sprawl and simplify operations, all while delivering advanced microsegmentation, workload isolation, and scalable performance.

License: Commercial

Key features include:

• Enhanced Security: Protects workloads with microsegmentation, workload isolation, and fine-grained policy enforcement.
• Comprehensive Observability: Provides real-time insights into traffic flows, DNS activity, and application behavior with in-product dashboards.
• Scalability and Performance: Supports multi-cluster and hybrid environments with efficient resource utilization and low-latency networking.
• Operational Simplicity: Simplifies policy creation and management through policy staging and automated enforcement.
• Multi-Cloud and Hybrid Support: Ensures consistent security and visibility across on-prem, cloud, and hybrid deployments.

2. Cisco ACI

Cisco Application Centric Infrastructure (ACI) is a software-defined networking (SDN) solution to simplify and improve modern data center and cloud operations. By capturing business intent as policies, Cisco ACI automates network, security, and infrastructure services, ensuring agility and resiliency in hybrid-cloud and multicloud environments.

License: Commercial

Key features include:

• Agility and automation: Automates IT workflows, supports rapid application delivery, and integrates with open APIs for operations.
• Enhanced security: Provides microsegmentation, zero-trust policies, and integration with Cisco security tools for consistent protection.
• Scalability and multicloud support: Enables hybrid and multicloud operations, ensures workload mobility, and supports global deployments.
• Operational simplicity: Offers real-time network monitoring, unified management policies, and programmable SDN fabric for simplified operations.
• Ecosystem integration: Works with Kubernetes, OpenStack, VMware, Azure, and other platforms to extend capabilities and ensure compatibility.

Source: Cisco

3. Juniper Contrail Networking

Juniper Contrail Networking is an SDN platform to automate the creation, management, and security of virtual networks in private, public, and hybrid cloud environments. By integrating with Kubernetes, OpenShift, and OpenStack, it enables centralized control and orchestration of routing, switching, security, and load balancing.

License: Apache-2.0
Repo: https://github.com/Juniper/contrail-networking

Key features include:

• Hybrid SDN orchestration: Centralized management for Kubernetes, OpenShift, and OpenStack environments.
• Cloud-native networking: Ensures operational consistency across bare-metal, private, and public cloud infrastructures.
• Routing and overlays: Supports flexible routing, virtual network overlays, and scalable topologies.
• Multi-cluster management: Enables federated control across Kubernetes clusters for efficient and unified operations.
• Automation and CI/CD integration: Incorporates NetOps practices with infrastructure-as-code and CI/CD pipelines for improved efficiency.

Source: Juniper

4. Open vSwitch (OVS)

Open vSwitch (OVS) is an open-source, multilayer virtual switch to support network automation and management capabilities in virtualized environments. It provides programmability while maintaining compatibility with standard protocols and interfaces like NetFlow, sFlow, and CLI. It supports distributed deployments across multiple physical servers.

License: Apache-2.0
Repo: https://github.com/openvswitch/ovs
GitHub stars: 3K+
Contributors: 400+

Key features include:

• Traffic visibility: Provides monitoring with NetFlow, sFlow, IPFIX, SPAN, and RSPAN support.
• Tunneling: Supports GRE, VXLAN, STT, and Geneve with optional IPsec encryption.
• VLAN and multicast support: Implements the 802.1Q VLAN model with trunking and multicast snooping.
• High availability: Features NIC bonding with options for active backup, source-MAC load balancing, and Layer 4 hashing.
• Protocol support: Offers OpenFlow support with virtualization-specific extensions and IPv6 compatibility.

5. Nutanix AHV

Nutanix AHV is an enterprise-grade virtualization solution integrated within the Nutanix Cloud Platform. It offers a secure and efficient environment for managing virtual machines (VMs) and containers across various infrastructures, including on-premises and public clouds.

License: Commercial with license-free virtualization options.

Key features include:

• Ease of management: Provides intuitive tools and automated workflows, simplifying the administration of VMs and containers.
• Enterprise capabilities: Includes features such as VM live migration, dynamic scheduling, high availability, and metro clustering to ensure robust performance and reliability.
• Cost efficiency: By eliminating the need for separate virtualization licensing, reduces operational costs without compromising functionality.
• Integrated security: Incorporates security measures like microsegmentation and compliance automation, enhancing the protection of virtualized environments.
• Unified control plane: Through Nutanix Cloud Manager, offers a single interface to manage virtualization, hyperconverged infrastructure, virtual networking, security, and automation.

Source: Nutanix

6. OpenNebula

OpenNebula is an open-source cloud and edge computing platform that simplifies the deployment and management of enterprise clouds. It provides a unified control panel to manage hybrid, multi-cloud, and edge environments, enabling organizations to avoid vendor lock-in while reducing operational complexity and costs. Users can leverage network masks, DNS servers, and gateways, to configure virtual machine networking.

License: Apache-2.0
Repo: https://github.com/OpenNebula/one
GitHub stars: 1K+
Contributors: 100+

Key features include:

• Unified management: Provides a single control panel for managing IT infrastructure across on-premises, hybrid, and edge environments.
• Lightweight and easy maintenance: Features a small footprint and offers a single enterprise-ready product with long-term commercial support.
• Hybrid and edge automation: Automatically deploys clusters on-premises and in the cloud within minutes, supporting true hybrid and edge setups.
• Kubernetes integration: Includes a CNF-certified K8s distribution for integration of Kubernetes clusters alongside virtual machine workloads.
• Distributed cloud architecture: Supports distributed cloud deployments across multiple geographic locations with tailored configurations for diverse workloads.
• Networking capabilities: Enables the creation of Virtual Networks, which map virtualized networks on top of physical ones. Virtual Network Definitions are built upon the physical network infrastructure, logical address space, and guest configuration attributes.

Source: OpenNebula

7. Harvester

Harvester is an open-source HCI solution built on Kubernetes, for operators seeking a modern, cloud-native platform. It runs on bare-metal servers and unifies virtualization, containerized workloads, and distributed storage into a single, efficient system. Leveraging Kubernetes, Harvester supports both virtual machines and containerized environments while integrating with Rancher for management.

License: Apache-2.0
Repo: https://github.com/harvester/harvester
GitHub stars: 3K+
Contributors: 60+

Key features include:

• Simple deployment: Ships as a bootable appliance image for easy installation on bare-metal servers using an ISO or iPXE scripts.
• VM management: Supports creating, editing, cloning, and deleting VMs with features like SSH-key injection, cloud-init, and live migration.
• Backup and recovery: Includes VM backup, snapshot, and restore capabilities using NFS, S3 servers, or NAS devices for high availability.
• Distributed storage: Provides block storage with tiering, allowing easy volume creation, editing, cloning, and exporting.
• Flexible networking: Offers virtual IPs, multiple NIC support, VLAN configuration, and external network connectivity for networking needs.
• KubeVirt networking layer: Handles the network paths between the Kubernetes pod and the VM, enabling communication within the cluster environment.
• Harvester networking layer: Supports connections between pods and the host network.
• External networking layer: Extends connectivity to external network devices, ensuring VMs can communicate beyond the cluster.
• Storage networking: Separates storage traffic from other cluster workloads, optimizing resource utilization and improving performance.

Source: Harvester

8. NVIDIA Cumulus Linux

NVIDIA Cumulus Linux is an open network operating system to automate, customize, and scale data center networks. Built on Linux, it provides a flexible and interoperable platform that simplifies network management while leveraging standard Linux-based tools.

License: Open source NVIDIA license

Key features include:

• Unnumbered interfaces: Simplifies automation with a simplified IP approach for BGP and OSPF using unified templates for spine and leaf nodes.
• Redistribute neighbor (RDNBR): Enables host and VM mobility by dynamically discovering servers at layer 3 without reconfiguration during relocations.
• Prescriptive topology manager (PTM): Accelerates deployment by verifying physical connections and resolving cabling issues efficiently.
• Virtual routing and forwarding (VRF): Supports multiple network paths on a single switch, offering traffic isolation and segmentation.
• Ethernet virtual private networks (EVPN): Enables the operation of legacy layer-2 applications over modern layer-3 network architectures.

Source: NVIDIA

Conclusion

When evaluating alternatives to VMware NSX, it’s essential to consider your organization’s specific needs, such as scalability, integration capabilities, security features, and ease of management. Open-source and commercial solutions alike offer diverse approaches to network virtualization, each with unique strengths and challenges.

By aligning the choice of platform with operational goals, existing infrastructure, and future scalability requirements, organizations can adopt a solution that delivers security and cost-effectiveness in managing modern networking environments.