Dell PowerConnect 8100 User's Configuration Guide - Page 847

console(config-if-Te1/0/1)#classofservice traffic-class-group 2 2 console(config-if-Te1/0/1)#traffic-class-group weight 30 70 0 console(config-if-Te1/0/1)#traffic-class-group strict 2 PC81xx Operation When DCBx is enabled on manually configured ports, it is not necessary for the ETS parameters to match, regardless of the version of DCBX negotiated or configured. Configuration mismatches are logged. In auto configuration mode, ETS parameters from the configuration source are checked (Max TCs 3 and bandwidth equal to 100%) and if the system is capable of performing the configuration, it is accepted and propagated as received to the other auto-configuration ports. The ETS Recommendation TLVs are preferred over the ETS Configuration TLVs. Auto-configuration via DCBX overrides manually configured ETS parameters for auto-configured ports, however, manual configuration is restored should the port be placed back into the manual port role. The ETS parameters received via DCBX are modified and applied to the system via the DCBX Mapping function as follows (references are to the 802.1Qaz parameters): • Like traffic classes are combined up to the limits of the system; e.g., no more than 2 lossless CoS queues may be configured. • The Priority Assignment Table (user priority to CoS queue mapping) is utilized by the system to map user priorities to the traffic classes (CoS queues). • The TSA Assignment Table is converted to use 3 TCGs internally. Priorities with like characteristics are combined into TCGs, i.e. strict priority traffic is combined into a TCG, lossless traffic is combined into a TCG, etc. Generally, strict priority traffic is mapped onto TCG 2, lossless traffic is mapped onto TCG1 and best effort traffic is mapped onto TCG0. • The bandwidths from the TC Bandwidth Table are summed based on the internal TCG mapping and are used to set the TCG weights. Other switches may assign bandwidth to strict priority queues. This bandwidth is counted in the sum to ETS 100% validation check, however, internally the weight for strict priority queues is ignored and they are configured for unlimited bandwidth. An implication of this assignment is that the percentage of bandwidth that may be consumed by a WDRR TCG after Configuring Data Center Bridging Features 847