Review cabling and configuration considerations

03/14/2025 Contributors

Before configuring your Broadcom BES-53248 switch, review the following considerations.

Cluster port switch assignments

You can use the Broadcom-supported BES-53248 cluster switch port assignments table as a guide to configure your cluster.

Switch ports	Ports usage
0-16	10/25GbE cluster port nodes, base configuration
17-48	10/25GbE cluster port nodes, with licenses
49-54	40/100GbE cluster port nodes, with licenses, added right to left
55-56	100GbE cluster Inter-Switch Link (ISL) ports, base configuration

See the Hardware Universe for more information on switch ports.

On BES-53248 cluster switches, the 48 10/25GbE (SFP28/SFP+) ports are combined into 12 x 4-port groups as follows: Ports 1-4, 5-8, 9-12, 13-16, 17-20, 21-24, 25-28, 29-32, 33-36, 37-40, 41-44, and 45-48.
The SFP28/SFP+ port speed must be the same (10GbE or 25GbE) across all ports in the 4-port group.
If speeds in a 4-port group are different, the switch ports will not operate correctly.

For 25G ports with copper cables, see the following table for details.

If the Controller side is auto, the switch side is set to FEC 25G.
For 25G ports with Fiber/Optical cables, see the following table for details:

Use the following command to set the 25G port FEC to either auto or fc, as required:

systemshell -node <node> -command sudo sysctl dev.ice.<X>.requested_fec=<auto/fc>

When set to auto:
- The auto setting propagates the setting to hardware immediately and no reboot is required.
- If bootarg.cpk_fec_fc_eXx already exists, it is deleted from the bootarg storage.
- After a reboot, the auto setting remains in place since auto is the default FEC setting.
When set to fc:
- The FC-FEC setting propagates the setting to the hardware immediately and no reboot is required.
- A new bootarg.cpk_fec_fc_eXx is created with the value set to "true".
- After a reboot, FC-FEC setting remains in place for the driver code to use.