Brocade Converged Enhanced Ethernet Administrator's Guide v6.1.2_cee (53-1001258-01, June 2009)

Converged Enhanced Ethernet Administrator’s Guide 117
53-1001258-01
Scheduling
8
Multicast queue scheduling
The multicast traffic classes are numbered from 0 to 3; higher numbered traffic classes are
considered higher priority. A fixed mapping from multicast traffic class to equivalent unicast traffic
class is applied to select the queue scheduling behavior. Table 21 presents the multicast traffic
class equivalence mapping applied.
Once the multicast traffic class equivalence mapping has been applied, then scheduling and any
scheduler configuration are inherited from the equivalent unicast traffic class. For example, with
an SP8 scheduling policy, multicast traffic class 3 is mapped to unicast traffic class 6 and referring
to Table 20 on page 116 shows it will inherit SP7 scheduling priority and multicast traffic class 2
inherits SP5 service, 1 = SP3, 0 = SP1. And SP4 scheduling policy multicast traffic class 3 inherits
SP3 service, 2 = SP1, 1 = WRR3, 0 = WRR1.
Unicast ingress and egress queueing utilizes a hybrid scheduler that simultaneously supports
SP+WRR service and multiple physical queues with the same service level. Multicast adds
additional multicast expansion queues. Since multicast traffic classes are equivalent to unicast
service levels, they're treated exactly as their equivalent unicast service policies.
Scheduling the QoS multicast queue
Example of setting the multicast Traffic Class packet expansion scheduler for Traffic Class 0 getting 10% bandwidth, Traffic
Class 1 getting 20% bandwidth, Traffic Class 2 getting 30% bandwidth, and Traffic Class 3 getting 40% bandwidth.
switch:admin>cmsh
switch>enable
switch#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
switch(config)#qos queue multicast scheduler dwrr 10 20 30 40
switch(config)#exit
switch#
TABLE 21 Multicast traffic class equivalence mapping
Multicast traffic class Equivalent unicast traffic class
36
24
12
00
Step Task Command
1 Enter global configuration mode.
switch#configure terminal
2 Specify the schedule to use and the traffic
class to bandwidth mapping.
switch(config)#qos queue multicast
scheduler dwrr 10 20 30 40