Configuration Guide User guide

FastIron Configuration Guide 1975
53-1002494-02
QoS queues
• DSCP to internal forwarding priority mapping – You can change the mapping between the
DSCP value and the internal forwarding priority value from the default values shown in
Table 336 through Table 339. This mapping is used for CoS marking and determining the
internal priority when the trust level is DSCP. Refer to “Changing the DSCP to internal
forwarding priority mappings” on page 1984.
• VLAN priority (802.1p) to hardware forwarding queue - You can change the mapping between
the 802.1p value and hardware forwarding queue from the default value. Refer to “Changing
the VLAN priority 802.1p to hardware forwarding queue mappings” on page 1985
User-configurable scheduler profile
The user-configurable scheduler profile is a template that defines either the scheduling
mechanism or scheduling profile (weights assigned to the queues) or both for the egress queues. A
configured user-configurable scheduler profile for egress queues can be applied to any hardware
device. The default QoS is applicable to the entire system. If the scheduler profile is configured
using the qos mech strict command, all devices in the system will be configured with the strict
priority. The user-configurable scheduler profile is applicable only to the specific devices, leaving
the remaining devices running default QoS. On any device, the user-configurable scheduler profile
has high priority over the default QoS. On any device, user-configurable scheduler profile has high
priority over the default QoS. The user-configurable scheduler profile should be in line with default
QoS commands in both stacking and stand-alone systems.
User-configurable scheduler profile configuration
Configuring a user-configurable scheduler profile involves, selecting a proper mechanism and
appropriate weights for the traffic classes (TCs) corresponding to that mechanism. It is highly
recommended that you let the system use the default scheduling mechanism unless user knows
what parameters you intend to modify and for what reasons.
There are two ways of creating a user-configurable scheduler profile. The scheduler-profile can be
created either by specifying a mechanism (WRR, Strict, or Mixed) or by specifying weights.
The user-configurable scheduler profile can be created by specifying a mechanism. There are three
available mechanisms:
• Strict Priority (SP)
• Weighted Round Robin (WRR)
• Mixed (combination of SP and WRR)
Following is the command format for creating a profile while specifying a mechanism.
qos scheduler-profile <user_profile_name> mechanism <scheduling_mechanism>
Syntax: :
The <user_profile_name> variable is the name of the profile you are creating.
The <scheduling_mechanism> variable is SP, WRR or Mixed.
The user-configurable scheduler profile can be created by specifying weights from qosp0 through
qosp7 as shown in the following command format.
qos scheduler-profile <user_profile_name> profile qosp0 <w0> …. qosp7 <w7>
Syntax: