configure forwarding switching-mode

configure forwarding switching-mode [cut-through | store-and-forward]


Configures the switching mode as either cut-through or store-and-forward.

Syntax Description

cut-through Specifies that a packet can begin being transmitted prior to its being received in full.
store-and-forward Specifies that a packet is transmitted only after the entire packet has been received and stored in the packet memory.



Usage Guidelines

Use this command to configure the switch to begin transmitting a packet before its entire contents have been received. This reduces the forwarding latency of the switch.

Cut-through mode cannot be achieved for packet sizes that are less than or equal to 384 bytes. On the Summit X770 and X670-G2, cut-through can be achieved for all packet sizes.

To display the switch mode settings, use the show forwarding configuration command.

When issued on a BlackDiamond 8800 series switch, this command does not affect module types other than those listed in the Platform Availability section below.


This command was first available in ExtremeXOS 12.3.

Platform Availability

This command is available on BlackDiamond X8 switches, BlackDiamond 8800 series switches with 8900-10G24X-c and 8900-MSM-128 series modules, and Summit X670, X670-G2, and X770.

The BlackDiamond 8900-G96T-c I/O module supports cut-through switching only in the switching fabric and impacts cross-chip and cross-slot switching only.