C1-N9K-C9396TXB18Q Cisco Nexus 9396TX Layer 3 Switch

Product Overview

The Cisco C1-N9K-C9396TXB18Q Nexus 9396TX is a high-performance Layer 3 network switch engineered for modern data centers. Built under the trusted Cisco Nexus 9300 Series, this switch delivers scalability, speed, and reliability for enterprise and cloud-based environments.

General Product Details

Manufacturer & Identification

• Manufacturer: Cisco Systems, Inc.
• Part Number: C1-N9K-C9396TXB18Q
• Product Line: Nexus
• Series: 9300 Series
• Model: 9396TX

Interfaces and Expansion Capabilities

Port Configuration

This Cisco Nexus switch offers a versatile port layout to support high-density networking requirements.

• Total Network Ports: 48
• 48 × 10 Gigabit Ethernet ports
• 12 × 40 Gigabit Ethernet expansion slots
• Modular architecture for future scalability

Expansion Slot Details

• Total Expansion Slots: 12
• Slot Type: QSFP+

Media Types and Performance

Supported Media Options

• Twisted Pair cabling
• Optical Fiber connectivity

Ethernet & Network Technologies

• 10 Gigabit Ethernet (10GbE)
• 40 Gigabit Ethernet (40GbE)
• 10GBase-T standard
• 40GBase-X architecture

Network Layer and Communication

Layer Support

• Supports Layer 3 routing functionality
• Optimized for advanced traffic management

Management and Control Features

Network Management

• Fully manageable switch
• Supports centralized network monitoring
• Ideal for enterprise IT administration

Power and Reliability

Power Specifications

• Primary Power Source: Power Supply Unit
• Redundant Power Supply: Supported
• Ensures continuous operation and high availability

Cisco Nexus 9396TX: The Foundation for Modern Data Center

The Cisco C1-N9K-C9396TXB18Q Nexus 9396TX Switch represents a pivotal evolution in top-of-rack (ToR) and middle-of-row data center switching. Engineered as a 1RU fixed-port switch within the renowned Cisco Nexus 9000 Series, the 9396TX is designed to deliver exceptional performance, operational simplicity, and seamless programmability for enterprise and cloud-scale environments. At its core, it provides 48 fixed 1/10GBASE-T copper ports and 12 fixed 40 Gigabit Ethernet QSFP+ uplink ports, offering a versatile and high-density connectivity solution. Built on Cisco's modular NX-OS software, this switch empowers organizations to transition from rigid, static architectures to agile, application-centric infrastructures, supporting both classic Cisco NX-OS and modern, open Cisco ACI (Application Centric Infrastructure) modes.

Architectural Design and Hardware Specifications

The physical and architectural design of the Cisco Nexus 9396TX is optimized for high performance in a compact form factor, making it an ideal candidate for space-constrained data center racks. Its robust hardware specifications ensure reliable switching and routing for the most demanding workloads.

Port Configuration and Density

The hallmark of the 9396TX model is its balanced and future-ready port configuration. The switch offers:

48 x 10GBASE-T RJ-45 Ports: These copper ports support 100M/1G/10G speeds, providing autonegotiation and backward compatibility. This makes them perfect for connecting servers with native 10GbE NICs, legacy 1GbE equipment, or for cost-effective cabling using standard Cat6a/Cat7 twisted-pair copper.
12 x 40 Gigabit Ethernet QSFP+ Uplink Ports: These high-bandwidth ports offer flexible connectivity options. Each QSFP+ port can operate as a native 40G interface or can be broken out into 4 x 10G lanes using a QSA adapter or appropriate splitter cables, effectively offering up to 96 x 10G ports in total. This enables high-speed aggregation to spine switches or core network infrastructure.

Performance and Switching Capacity

Underpinning the port density is a non-blocking switching fabric designed to handle line-rate traffic on all ports simultaneously.

Aggregate Throughput: 1.44 Tbps
Forwarding Rate: Over 1 billion packets per second (Bpps)
Latency: Consistently low latency, typically in the range of a few microseconds, which is critical for high-frequency trading, clustered applications, and storage traffic.

Redundancy and Reliability Features

To ensure maximum uptime, the 9396TX incorporates several carrier-class reliability features:

Hot-Swappable, Redundant Power Supplies: Supports N+1 and N+N power redundancy with front-to-back or back-to-front airflow options.
Hot-Swappable, Redundant Fan Trays: Field-replaceable fan modules with multiple airflow schemes to match data center cooling designs.
In-Service Software Upgrades (ISSU): Allows for software patches and upgrades with minimal to no disruption to network operations.

Software Capabilities with Cisco NX-OS

The Cisco Nexus 9396TX runs the mature, resilient Cisco NX-OS operating system, providing a robust feature set that extends far beyond basic Layer 2 switching.

Comprehensive Layer 2 and Layer 3 Feature Set

The switch operates as a full-featured Layer 3 switch, supporting a comprehensive suite of protocols for complex network designs.

Advanced Layer 2 Protocols

Virtual PortChannel (vPC): Cisco's flagship multi-chassis link aggregation technology eliminates the Spanning Tree Protocol blocked ports, allowing active-active utilization of all uplinks from two separate Nexus switches.
Cisco FabricPath: Provides a scalable, low-latency Layer 2 multipath network for fabric architectures, simplifying network design and improving utilization.
Comprehensive Ethernet Features: Robust support for 802.1Q VLANs, 802.1p CoS, 802.3ad Link Aggregation (LACP), and various Spanning Tree protocols (RSTP, MSTP).

Enterprise-Grade Layer 3 Routing

Dynamic Routing Protocols: Full support for OSPF, EIGRP, BGP (for WAN/Data Center Interconnect), and IS-IS for fabric underlays.
Multicast Routing: Feature-rich PIM Sparse Mode, BiDir, and Source-Specific Multicast (SSM) for efficient video distribution and financial data feeds.
VRF-Lite: Enables network segmentation and multi-tenancy by allowing multiple routing and forwarding tables to coexist on a single physical switch.

Network Virtualization and Overlay Technologies

The 9396TX is built for modern, virtualized data centers.

VXLAN Gateway Functionality: Acts as a VXLAN Layer 2 and Layer 3 gateway, bridging physical and virtual workloads. It supports VXLAN bridging and routing with MP-BGP EVPN control plane, essential for creating large, flexible Layer 2 domains over a scalable Layer 3 underlay.
Integration with VMware Environments: Features like Cisco Nexus 1000V InterConnect and VM-FEX (Virtual Machine Fabric Extender) provide advanced policy and visibility for virtual machines.

Application Centric Infrastructure (ACI) Mode

When deployed as part of a Cisco ACI fabric, the 9396TX transforms into a leaf switch managed centrally by the Cisco Application Policy Infrastructure Controller (APIC). In this mode:

Policy-Driven Automation: Network, security, and application policies are defined in a centralized, intent-based model and pushed automatically to the switch.
Integrated Visibility: Provides deep application-level telemetry and health scores, correlating network events with application performance.
Open Ecosystem: ACI integrates with hypervisors, cloud platforms, and third-party application directors for a holistic automation framework.

Advanced Features for Data Center Operations

Beyond core switching and routing, the Nexus 9396TX includes a suite of features that enhance security, visibility, and ease of management.

Enhanced Security Posture

The switch provides a multi-layered security approach to protect the data center infrastructure.

Role-Based Access Control (RBAC): Granular control over administrator permissions.
IEEE 802.1X: For network access control, authenticating devices and users before granting network access.
ACLs and Security Group Tags (SGTs): Traditional ACLs for traffic filtering, and in ACI mode, scalable SGTs for logical group-based policies.
CoPP (Control Plane Policing): Protects the switch's CPU from malicious traffic and denial-of-service attacks.

Deep Visibility and Telemetry

Operational insight is critical for troubleshooting and performance optimization.

Embedded Event Manager (EEM): Allows automation of scripts and policies based on specific network events.
NetFlow and Flexible NetFlow: For detailed traffic analysis and monitoring.
SPAN and ERSPAN: Local and remote port mirroring for traffic analysis tools.
Advanced Buffer Monitoring: Tools to monitor queue depths and buffer utilization, crucial for diagnosing microbursts and congestion.

Streamlined Management and Automation

The switch is designed for modern network operations (NetOps) and DevOps practices.

Programmatic Interfaces: Full support for Python scripting, RESTful APIs, JSON/XML, and OpenConfig models, enabling automation with tools like Ansible, Puppet, or Chef.
Cisco DCNM Integration: Provides a single pane of glass for lifecycle management, provisioning, and monitoring of standalone NX-OS switches.
Zero-Touch Provisioning (ZTP): Simplifies large-scale deployments by automating the initial configuration and software image installation process.

Ideal Use Cases and Applications

The versatility of the Cisco Nexus 9396TX makes it suitable for a wide array of data center applications.

High-Density 10GbE Server Access (ToR)

Its primary role is as a high-performance Top-of-Rack switch, connecting a rack of servers with 10GbE connectivity and providing high-bandwidth 40G uplinks to the spine or core layer. The 10GBASE-T ports are particularly advantageous for connecting mainstream servers with built-in copper NICs.

Storage Network Connectivity

With its high throughput and low latency, the 9396TX is an excellent platform for IP-based storage networks (NAS, iSCSI). Features like jumbo frame support and advanced QoS ensure storage traffic is handled efficiently and with priority.

Enterprise and Private Cloud Fabric

When deployed in a leaf-spine architecture—either with traditional NX-OS or as part of an ACI fabric—multiple 9396TX switches form a scalable, low-latency Clos network. This fabric supports multi-tenancy, dynamic workload placement, and seamless integration with hypervisors from VMware, Microsoft, and open-source platforms.

Big Data and High-Performance Computing (HPC) Clusters

The non-blocking architecture and high packet-forwarding rate make it suitable for big data analytics clusters (e.g., Hadoop, Spark) and HPC environments where east-west traffic between nodes is immense and latency-sensitive.