Dell EMC Networking – Deploying Data Center Bridging Guide for deploying DCB in a typical Data Center Abstract A short Data Center Bridging (DCB) cheat sheet configuration with Dell EMC Networking OS10 September 2018 Dell EMC Technical White Paper
Data Center Bridging Revisions Date Description September 2018 Initial release Acknowledgements This paper was produced by the following members of the Dell EMC networking technical marketing engineering team: Author: Mario Chow Support: Other: N/A The information in this publication is provided “as is.” Dell Inc.
Table of contents Revisions.............................................................................................................................................................................2 Acknowledgements .............................................................................................................................................................2 Executive summary.....................................................................................................................
Executive summary The data center has always been a critical component of the IT infrastructure of enterprise organizations. Ethernet has been, and will most likely continue to be, the dominant network protocol in data centers for server-to-server communication. Data centers are facing increasing performance demands and are also embracing convergence to address consolidation. These factors require traffic patterns that ensure lossless delivery of packets in the network with no packet loss.
1 Data Center Bridging Data-Center Bridging (DCB) is an extension to the Ethernet protocol that makes dedicated traffic flows possible in a converged network scenario. DCB distinguishes traffic flows by tagging the traffic with a specific value (0-7) for Class of Service (CoS) or (0-63) for Differentiated Services Code Point (DSCP).
1.3 Enhanced Transmission Selection (802.1Qaz) The third enhancement specifies enhancement of transmission selection to support allocation of bandwidth amongst traffic classes. When the offered load in a traffic class does not use its allocated bandwidth, enhanced transmission selection allows other traffic classes to use the available bandwidth. The-bandwidth allocation priorities coexist with strict priorities. Networks prioritize traffic to provide different service characteristics to traffic classes.
2 Test setup Figure 1 shows the setup used to test DCB, PFC, and ETS. The following list defines the setup: • • • • • • Traffic is bi-directional. Traffic is between two operating systems – OS9 {9.13(0.0) & OS10 (10.4.0E(X2)}. Priority Flow Control is “ON” with iSCSI traffic and “OFF” with LAN traffic. ETS is set to 1% for LAN traffic, 99% for iSCSI traffic. DCB is on at both ends.
A Appendix A.1 Configuration details This section provides the details about the configurations applicable on all the switches. Component table example Component Description Operating system Dell OS 9 and 10 Application IXExplorer 6.70 - IXIA Switch S4048-ON, S4128F-ON OS 9 based switch configuration – Switch on the left side labeled “S4048-ON-3” 1. Trust the dot1p Class of service values to queue assignment configured by the operating system. a. Switch(config)# service-class dynamic dot1p 2.
OS10 based switch configuration – All other switches besides “S4048-ON-3” 1. Turn on DCBx on the switch. a. Switch# conf t b. Switch(config# dcbx en 2. Turn on ETS. a. Switch(config)# system qos b. Switch(config-sys-qos)# ets mode on c. Switch(config-sys-qos)# end d. Switch# 3. Configure the qos-map to match the queues to the CoS values a. Switch# conf t b. Switch(config)# qos-map traffic-class qmap c. Switch(config-qos-map)# queue 0 qos-group 0-3,5-7 d. Switch(config-qos-map)# queue 4 qos-group 4 4.
a. b. c. d. e. Switch# conf t Switch(config)# policy-map type network-qos temp Switch(config-pmap-network-qos)# class temp Switch(config-pmap-c-nqos)# pause Switch(config-pmap-c-nqos)# pfc-cos 4 6. Applying policy maps to interfaces a. Switch# conf t b. Switch(config# inte ethe1/1/53 – interface part of iSCSI flows. c. Switch(config-if-eth1/1/53)# switchport mode trunk d. Switch(config-if-eth1/1/53)# switchport trunk allowed vlan 100,200 – LAN and iSCSI traffic allowed in this interface. e.
A.2 Appendix The two following configurations apply to the switches in Figure 1. S4048-ON-3 (OS9) Trust system wide 802.1p settings mappings to CoS values. Enable all queues as Priority Flow Control-enabled. Create the DCB map specifying PFC and ETS. Then assign the priority group to the proper class of service. Assign the DCB map to all active interfaces.
S4048-ON-4 (OS10) Enable DCBx. Turn on ETS. Configure policy maps with accompanying class maps. Class maps MUST be configured first and then attached to the policy maps.
