Hi,

Version 10.5.2.0

Booted up a S4148F-on for the first time and noticed that 4 QSFP28 ports are set to 100G by default:

interface breakout 1/1/25 map 100g-1x
interface breakout 1/1/26 map 100g-1x
interface breakout 1/1/29 map 100g-1x
interface breakout 1/1/30 map 100g-1x

According to the switches' datasheet, the 6 QSFP28 ports can be configured for 40G. When trying to set this though, the option is not available:

(config)# interface breakout 1/1/25 map
100g-1x Breakout to 1 100G interface
50g-2x Breakout to 2 50G interfaces
25g-4x Breakout to 4 25G interfaces
10g-4x Breakout to 4 10G interfaces

Also, just testing the configuration of all 6 ports, the original 4 ports can be configured, but when trying to setup the middle ports, I get:

# interface breakout 1/1/27 map 25g-4x
% Error: Illegal parameter.

There does not seem to be any documentation on this.

Thanks!