Reference Architecture

Page 16
Broadcom NDCs in the PowerEdge M620 blade servers, and the EqualLogic PS6110 storage controllers.
The DCB settings are not propagated to the Force10 S55 out-of-band management switch and the
associated out-of-band management ports but the out-of-band management traffic going to the core
from Force10 S55 switch traverses through the Force10 S4810 switches. When the out-of-band
management traffic traverses through the Force10 S4810 switches, it obeys the DCB settings.
DCB technologies enable each switch-port and each network device-port in the converged network to
simultaneously carry multiple traffic classes, while guaranteeing performance and QoS. In case of
Active System 800v, DCB settings are used for the two traffic classes: (i) Traffic class for iSCSI traffic,
and (ii) Traffic class for all non-iSCSI traffic, which, in the case of Active System 800v, are different
LAN traffic types. DCB ETS settings are configured to assign bandwidth limits to the two traffic classes.
These bandwidth limitations are effective during periods of contention between the two traffic classes.
The iSCSI traffic class is also configured with Priority Flow Control (PFC), which guarantees lossless
iSCSI traffic.
The Broadcom Network Adapters and the Broadcom NDCs support DCB and DCBX. This capability, along
with iSCSI hardware offload, allows Active System 800v solution to include an end-to-end converged
network design, without requiring support from the VMware vSphere hypervisor for DCB.
Figure 5 below provides a conceptual view of converged traffic with Data Center Bridging in Active
System 800v.
Figure 5: Conceptual View of Converged Traffic Using DCB
Virtual Link Trunking (VLT) for S4810s: Inside each Active System 800v, a Virtual Link Trunking
interconnect (VLTi) is configured between the two Force10 S4810 switches using the Virtual Link
Trunking (VLT) technology. VLT peer LAGs are configured between the PowerEdge M I/O Aggregator
modules and Force10 S4810 switches, and also between the Force10 S4810 switch and the Force10
S4810 switches.
Virtual Link Trunking technology allows a server or bridge to uplink a single trunk into more than one
Force10 S4810 switch, and to remain unaware of the fact that the single trunk is connected to two
different switches. The switches, a VLT-pair, make themselves appear as a single switch for a