Huawei S6720 Switch Aggregation and Stacking

Huawei S6720 switches support service port stacking with up to nine switches, enabling simplified management, redundancy, and scalable bandwidth.

Stacking Overview

Huawei S6720-LI and S6720S-LI switches can form stacks using dedicated stack cables in service port stacking mode, allowing multiple physical switches to operate as a single logical device with one IP address for management . Stacking provides synchronized configurations, cross-device link aggregation (Eth-Trunk), and redundancy, with a master switch managing the stack and standby switches taking over if the master fails .

Supported Stack Topologies

• Ring topology: Recommended for redundancy, providing dual-link paths to prevent single points of failure .
• Chain topology: Simpler but less resilient, as a single failure can disrupt the stack .
• Stack size: 2 to 9 switches are supported, but when using iMaster NCE-Campus for management, a maximum of 4 switches is recommended .
• Compatibility: S6720-LI switches can stack with other S6720-LI models, and S6720S-LI with S6720S-LI, but cross-stacking between LI and S-LI models is not supported .

Port and Cable Requirements

• Dedicated stack ports must be used; combo ports cannot serve as stack member ports .
• Certified stack cables (e.g., QSFP-40G-Stack) are recommended to avoid errors or instability .
• Some service ports can be configured as stack ports, while others remain ordinary service ports .
• Bidirectional links are advised for redundancy, and member IDs and priorities should be set before connecting stack cables .

Aggregation Features

• Eth-Trunk allows multiple physical links to be aggregated across stack members, increasing bandwidth and providing link-level redundancy .
• S6720S models support 10 GE and 40 GE uplinks, suitable for high-performance aggregation in campus or server farm environments .
• Hybrid stacking is supported via 10 GE/QSFP ports, enabling flexible deployment and integration with SVF-enabled supervisors for logical fabric creation .

Best Practices

• Ensure uniform VRP firmware versions across all stack members .
• Enable auto-upgrade to synchronize firmware and configurations.
• Backup configurations externally using FTP or TFTP before stacking .
• Validate configurations in a lab environment before production deployment.
• Use ring topology whenever possible to maximize redundancy and minimize downtime .

Management and Monitoring

• Stacks can be managed via iMaster NCE-Campus or traditional CLI, providing centralized monitoring, fault management, and energy-saving features .
• The master switch handles configuration distribution, while standby switches ensure continuity in case of failure . By following these guidelines, Huawei S6720 switches can be deployed in resilient, high-performance aggregation stacks, simplifying network management and scaling efficiently for enterprise or campus networks .