Configuring Hierarchical CoS on vMX
To configure hierarchical CoS, perform these tasks:
Enabling Flexible Queuing
Hierarchical CoS is disabled by default. To enable hierarchical
CoS, include the flexible-queuing-mode
statement at the [edit chassis fpc 0]
hierarchy level and restart the FPC.
[edit] user@vmx# set chassis fpc 0 flexible-queuing-mode
Mapping Forwarding Classes to Queues on vMX
You must map all configured forwarding classes to one of the queues.
[edit] user@vmx# set class-of-service forwarding-classes class class-name queue-num queue-number
Configuring Traffic Control Profiles for vMX
Traffic control profiles support only the shaping-rate
and scheduler-map
statements for vMX.
To specify the shaping rate, include the shaping-rate
statement at the [edit class-of-service traffic-control-profiles profile-name]
hierarchy level.
[edit] user@vmx# set class-of-service traffic-control-profiles profile-name shaping-rate rate
To specify the scheduler map, include the scheduler-map
statement at the [edit class-of-service traffic-control-profiles profile-name]
hierarchy level.
[edit] user@vmx# set class-of-service traffic-control-profiles profile-name scheduler-map map-name
Configuring Schedulers on vMX
The scheduler map contains the mapping of forwarding classes to their schedulers. The scheduler defines the properties for the queue.
Schedulers support only the transmit-rate
and excess-rate proportion
statements for vMX.
To specify the transmission rate, include the transmit-rate
statement at the [edit class-of-service schedulers scheduler-name]
hierarchy level.
[edit] user@vmx# set class-of-service schedulers scheduler-name transmit-rate rate
Guaranteed rate is not supported, so there is no reserved bandwidth for the VLAN. To get the expected behavior, we recommend that you configure the transmit rate to be the guaranteed rate.
To specify the proportion of the excess bandwidth to share,
include the excess-rate proportion
statement at the [edit class-of-service schedulers scheduler-name]
hierarchy level. The value is in the range of 0 through 1000.
[edit] user@vmx# set class-of-service schedulers scheduler-name excess-rate proportion value
If you configure the excess rate for one queue, the excess rate is expected for all the queues to compute the weights. If the excess rate is not configured, the default weight of 1 is used.
To get the expected behavior, you must configure the excess rate for all queues.
For example, if you configure excess rate for the low-priority queues, configure the same excess rate for the high- and medium-priority queues.