Connectivity Guide

11 Enable ECN globally.
OS10(config-sys-qos)#random-detect ecn
After you enable ECN globally, ECN marks the CE bit of the ECN eld in a packet as ECT.
In the S4200–ON Series platform, congure separate thresholds for ECN capable trac (ECT). If you enable ECN, ECT is marked based
on the congured ECN threshold and non-ECT drops based on the WRED thresholds.
Storm control
Trac storms created by packet ooding or other reasons may degrade the performance of the network. The storm control feature allows
you to control unknown unicast, multicast, and broadcast trac on L2 and L3 physical interfaces.
In the storm control unknown unicast conguration, both the unknown unicast and unknown multicast trac are rate-limited.
OS10 devices monitor the current level of the trac rate at xed intervals, compares the trac rate with the congured levels, and drops
excess trac.
By default, storm control is disabled on all interfaces. Enable storm control using the storm-control { broadcast | multicast
| unknown-unicast } rate-in-pps command in INTERFACE mode.
NOTE: On the S5148F-ON platform, there is a 2% of deviation in storm control conguration.
• Enable broadcast storm control with a rate of 1000 packets per second (pps) on Ethernet 1/1/1.
OS10(conf-if-eth1/1/1)# storm-control broadcast 1000
RoCE for faster access and lossless connectivity
Remote Direct Memory Access (RDMA) enables memory transfers between two computers in a network without involving the CPU of
either computer.
RDMA networks provide high bandwidth and low latency without any appreciable CPU overhead for improved application performance,
storage and data center utilization, and simplied network management. RDMA was traditionally supported only in an InniBand
environment. Currently, RDMA over Converged Ethernet (RoCE) is also implemented in data centers that use Ethernet or a mixed-protocol
environment.
OS10 devices support RoCE v1 and RoCE v2 protocols.
• RoCE v1 – An Ethernet layer protocol that allows for communication between two hosts that are in the same Ethernet broadcast
domain.
• RoCE v2 – An Internet layer protocol that allows RoCE v2 packets to be routed, called Routable RoCE (RRoCE).
To enable RRoCE, congure the QoS service policy on the switch in ingress and egress directions on all the interfaces. For more information
about this conguration, see Congure RoCE on the switch.
Congure RoCE on the switch
The following example describes the steps that you need to perform to congure RoCE on the switch. This conguration example uses
priority 3 for RoCE.
1 Enter in to the CONFIGURATION mode.
OS10# configure terminal
OS10 (config)#
2 Enable the Data Center Bridging Exchange protocol (DCBX).
OS10 (config)# dcbx enable
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Quality of service