Huawei S5720 optical port stacking

Huawei S5720 switches support optical port stacking using SFP/SFP+ ports, with up to four service ports per switch as stack member ports.

Overview of Optical Port Stacking

Huawei S5720 series switches allow stacking via SFP/SFP+ optical ports starting from VRP version V200R010. Two SFP+ optical ports can be configured as stack member ports, enabling multiple switches to operate as a single logical device. This provides simplified management, redundancy, and scalable bandwidth .

Key Limitations and Requirements

• Firmware Version: Optical port stacking requires VRP V200R010 or later. Downgrading to V200R009 or earlier requires removing stack member port configurations to avoid stack failures .
• Logical Stack Ports: Each switch supports a maximum of two logical stack ports, with each logical stack port containing one or two stack member ports. A switch can use up to four service ports as stack member ports .
• Stack Topology: For two switches, a chain (back-to-back) connection is sufficient. For three or more switches, a ring topology is recommended to ensure redundancy .
• Cable Types: SFP+ passive high-speed copper cables (1 m or 3 m) can be used, and their speed can be increased to 12 Gbit/s using the stack port speed command. Note that switches using 12 Gbit/s ports cannot stack with switches using 10 Gbit/s ports .
• Port Pairing: When a logical stack port contains two stack member ports, only ports 1 and 2 or ports 3 and 4 can be paired together .

Configuration Steps

1. Prepare Ports: Shut down the SFP/SFP+ ports intended for stacking.
2. Assign Stack Member Ports: Configure the optical ports as stack member ports using the VRP CLI.
3. Set Stack IDs and Priorities: Assign unique stack IDs and configure priorities to determine the master switch. For example:

   CodeCopy stack slot 0 priority 200 stack slot 0 renumber 1 stack slot 0 renumber 2

4. Connect Switches: Use optical cables to connect the logical stack ports according to the chosen topology (chain or ring).
5. Verify Stack: After powering on, check the stack status to ensure all members are recognized and operational.

Best Practices

• Topology: Use a ring topology for three or more switches to prevent single points of failure .
• Firmware Consistency: Ensure all switches in the stack run the same VRP version.
• Pre-Configuration: Configure stack member ports on new switches before connecting them to the stack to avoid packet loops caused by ACL resource limitations .
• Monitoring: Use display stack and display interface commands to monitor stack health and optical port status . By following these guidelines, Huawei S5720 switches can be effectively stacked using optical ports, providing high-speed interconnects and simplified network management.