Users Guide

NOTE: CIN supports only the dot1p priority-queue assignment in a priority group. To configure a dot1p priority
flow in a priority group to operate with link strict priority, you configure: The dot1p priority for strict-priority
scheduling (strict-priority command). The priority group for strict-priority scheduling (scheduler
strict command.
Configuring Bandwidth Allocation for DCBx CIN
After you apply an ETS output policy to an interface, if the DCBx version used in your data center network is CIN, you may need to
configure a QoS output policy to overwrite the default CIN bandwidth allocation.
This default setting divides the bandwidth allocated to each port queue equally between the dot1p priority traffic assigned to the queue.
To create a QoS output policy that allocates different amounts of bandwidth to the different traffic types/ dot1p priorities assigned to a
queue and apply the output policy to the interface, follow these steps.
1. Create a QoS output policy.
CONFIGURATION mode
Dell(conf)#qos-policy-output test12
The maximum 32 alphanumeric characters.
2. Configure the percentage of bandwidth to allocate to the dot1p priority/queue traffic in the associated L2 class map.
QoS OUTPUT POLICY mode
Dell(conf-qos-policy-out)#bandwidth-percentage 100
The default is none.
3. Repeat Step 2 to configure bandwidth percentages for other priority queues on the port.
QoS OUTPUT POLICY mode
Dell(conf-qos-policy-out)#bandwidth-percentage 100
4. Exit QoS Output Policy Configuration mode.
QoS OUTPUT POLICY mode
Dell(conf-if-te-0/1)#exit
5. Enter INTERFACE Configuration mode.
CONFIGURATION mode
interface type slot/port
6. Apply the QoS output policy with the bandwidth percentage for specified priority queues to an egress interface.
INTERFACE mode
Dell(conf-if-te-0/1)#service-policy output test12
Configuring ETS in a DCB Map
A 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 an interface.
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.
NOTE: You can configure only three priority groups in the S4048T-ON platform.
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.
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Data Center Bridging (DCB)