Users Guide

Table Of Contents
Broadcom NetXtreme-E-UG304-2CS
109
NetXtreme-E User Guide User Guide for Dell Platforms
14.2.5.1 Using the Section
This section is intended to provide information on the process of configuring a new server for RoCE use with RoCEv2
enabled, Congestion Control enabled, and optionally, PFC enabled and configured.
Any installation of other vendor's proprietary Infiniband software stack should be removed before proceeding with this
section.
14.2.5.2 Understanding Congestion Control
14.2.5.2.1 Basic Topology
Congestion control topology provides a basic topology of how to test congestion control. In this topology, there are two
senders transmitting packets at 25G to a receiver that can only receive at 25G.
Figure 39: Congestion Control Topology
14.2.5.2.2 Background
Congestion control flow provides a simple overview of ECN congestion management.
1. After ECN has been configured and enabled, the ECN bits in the IP header of RoCEv2 packets are either ECT1(01b) or
ECT0 (10b) based on the user configuration.
TOR
Receiver (2) Senders
Congestion
25G
25G
25G
Notification
Point
Reaction
Points