Reference Guide

• ETS TLVs are supported in DCBx versions CEE and IEEE2.5.
• The DCBx port-role configurations determine the ETS operational parameters (refer to Configure a
DCBx Operation).
• ETS configurations 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 configurations are ignored and existing ETS configurations are reset to the default ETS
settings.
• ETS operates with legacy DCBx versions as follows:
– In the CEE version, the priority group/traffic class group (TCG) ID 15 represents a non-ETS priority
group. Any priority group configured with a scheduler type is treated as a strict-priority group and
is given the priority-group (TCG) ID 15.
Configuring ETS in a DCB Map
switch supports the use of a DCB map in which you configure enhanced transmission selection (ETS)
setting. To configure ETS parameters, you must apply a DCB map on interface. This functionality is
supported on the platform.
ETS Configuration Notes
ETS provides a way to optimize bandwidth allocation to outbound 802.1p classes of converged Ethernet
traffic. Different traffic types have different service needs. Using ETS, you can create groups within an
802.1p priority class to configure different treatment for traffics with different bandwidth, latency, and
best-effort needs.
When you configure ETS in a DCB map:
• The DCB map associates a priority group with a PFC operational mode (on or off) and an ETS
scheduling and bandwidth allocation. You can apply a DCB map on multiple egress ports.
• Use the ETS configuration associated with 802.1p priority traffic in a DCB map in DCBx negotiation
with ETS peers.
• Traffic in priority groups is assigned to strict-queue or weighted round-robin (WRR) scheduling in an
ETS configuration and is managed using the ETS bandwidth-assignment algorithm. Dell Networking
OS de-queues all frames of strict-priority traffic before servicing any other queues. A queue with
strict-priority traffic can starve other queues in the same port.
• ETS-assigned bandwidth allocation and strict-priority scheduling apply only to data queues, not to
control queues.
• Dell Networking OS supports hierarchical scheduling on an interface. The control traffic on Dell
Networking OS is redirected to control queues as higher priority traffic with strict priority scheduling.
After the control queues drain out, the remaining data traffic is scheduled to queues according to the
bandwidth and scheduler configuration in the DCB map. The available bandwidth calculated by the
ETS algorithm is equal to the link bandwidth after scheduling non-ETS higher-priority traffic.
• The configuration of bandwidth allocation and strict-queue scheduling is not supported at the same
time for a priority group.
• Bandwidth assignment: By default, equal bandwidth is assigned to each dot1p priority in a priority
group. To configure the bandwidth assigned to the port queues associated with dot1p priorities in a
priority group, use the bandwidth percentage parameter. The sum of the bandwidth allocated to all
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Data Center Bridging (DCB)