Setup Guide

ETS Operation with DCBx
The following section describes DCBx negotiation with peer ETS devices.
In DCBx negotiation with peer ETS devices, ETS conguration is handled as follows:
• ETS TLVs are supported in DCBx versions CIN, CEE, and IEEE2.5.
• The DCBx port-role congurations determine the ETS operational parameters (refer to Congure a DCBx Operation).
• ETS congurations received from TLVs from a peer are validated.
• If there is a hardware limitation or TLV error:
– DCBx operation on an ETS port goes down.
– New ETS congurations are ignored and existing ETS congurations are reset to the default ETS settings.
• ETS operates with legacy DCBx versions as follows:
– In the CEE version, the priority group/trac class group (TCG) ID 15 represents a non-ETS priority group. Any priority group
congured with a scheduler type is treated as a strict-priority group and is given the priority-group (TCG) ID 15.
– The CIN version supports two types of strict-priority scheduling:
◦ Group strict priority: Use this to increase its bandwidth usage to the bandwidth total of the priority group and allow a single
priority ow in a priority group. A single ow in a group can use all the bandwidth allocated to the group.
◦ Link strict priority: Use this to increase to the maximum link bandwidth and allow a ow in any priority group.
CIN supports only the dot1p priority-queue assignment in a priority group. To congure a dot1p priority ow in a priority group to
operate with link strict priority, you congure: The dot1p priority for strict-priority scheduling (strict-priority command). The
priority group for strict-priority scheduling (
scheduler strict command.
Congure a DCBx Operation
DCB devices use data center bridging exchange protocol (DCBx) to exchange conguration information with directly connected peers
using the link layer discovery protocol (LLDP) protocol.
DCBx can detect the misconguration of a peer DCB device, and optionally, congure peer DCB devices with DCB feature settings to
ensure consistent operation in a data center network.
DCBx is a prerequisite for using DCB features, such as priority-based ow control (PFC) and enhanced trac selection (ETS), to exchange
link-level congurations in a converged Ethernet environment. DCBx is also deployed in topologies that support lossless operation for FCoE
or iSCSI trac. In these scenarios, all network devices are DCBx-enabled (DCBx is enabled end-to-end).
• Congure Enhanced Transmission Selection
DCBx supports the following versions: CIN, CEE, and IEEE2.5.
DCBx is not supported on PE ports and C9010 cascade ports (member ports in the C9010 LAG created to connect to an attached
C1048P).
Prerequisite: For DCBx, enable LLDP on all DCB devices.
DCBx Operation
DCBx performs the following operations:
• Discovers DCB conguration (such as PFC and ETS) in a peer device.
• Detects DCB mis-conguration in a peer device; that is, when DCB features are not compatibly congured on a peer device and the
local switch. Mis-conguration detection is feature-specic because some DCB features support asymmetric conguration.
• Recongures a peer device with the DCB conguration from its conguration source if the peer device is willing to accept
conguration.
Data Center Bridging (DCB)
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