Ets Operation With Dcbx; Bandwidth Allocation For Dcbx Cin - Dell PowerEdge M IO Aggregator Command Reference Manual

• When an ETS output policy is applied to an interface, ETS-configured scheduling and bandwidth
allocation take precedence over any auto-configured settings in the QoS output policies.
• ETS is enabled by default with the default ETS configuration applied (all dot1p priorities in the
same group with equal bandwidth allocation).

ETS Operation with DCBX

In DCBX negotiation with peer ETS devices, ETS configuration is handled as follows:
• ETS TLVs are supported in DCBX versions CIN, CEE, and IEEE2.5.
• ETS operational parameters are determined by the DCBX port-role configurations.
• ETS configurations received from TLVs from a peer are validated.
• In case of 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 previously
configured ETS output policy on the port or to the default ETS settings if no ETS output policy
was previously applied.
• 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.
• The CIN version supports two types of strict-priority scheduling:
CIN supports only the default dot1p priority-queue assignment in a priority group.

Bandwidth Allocation for DCBX CIN

After an ETS output policy is applied to an interface, if the DCBX version used in your data center
network is CIN, a QoS output policy is automatically configured 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.
62 | Data Center Bridging (DCB)
— Group strict priority: Allows a single priority flow in a priority group to increase its
bandwidth usage to the bandwidth total of the priority group. A single flow in a group can
use all the bandwidth allocated to the group.
— Link strict priority: Allows a flow in any priority group to increase to the maximum link
bandwidth.