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Classification
Configuring QoS
page 25-8
OmniSwitch AOS Release 7 Network Configuration Guide
June 2013
Configuring Automatic Prioritization for IP Phone Traffic
command is used to enable or disable automatic prioritization of IP phone traffic. In addi-
tion, this command also specifies whether to trust the IP phone traffic (the default) or apply a specified
priority value to the traffic. For example, the following command specifies a priority value to apply for
ingress IP phone traffic:
-> qos phones priority 1
To trust IP phone traffic, enter the following command:
-> qos phones trusted
To disable automatic IP phone traffic prioritization for the switch, enter the following command:
-> qos no phones
Note that When automatic prioritization of IP phone traffic is enabled, QoS policies that specify priority
are not applied to the IP phone traffic. Other QoS policies, however, are applied to this type of traffic as
usual. If a policy specifies rate limiting, then the policy with the lowest rate limiting value is applied.
Prioritizing CPU Packets
In addition to physical switch ports, each NI has an internal CPU interface that handles traffic sent to or
from the CPU (for example, BPDU and LAG PDUs). Such packets go directly to the CPU via a set of
queues without traversing the switch fabric. In addition, packets from the CPU go directly to local ports
without going through the fabric.
The QoS CPU priority policy action is used in a policy to assign a priority value to traffic destined for the
CPU. See the
command page in the
OmniSwitch CLI Reference Guide
for more
information.
Configuring Trusted Ports
By default switch ports are
untrusted
; that is, they do not recognize 802.1p or ToS/DSCP settings in pack-
ets of incoming traffic. When a port is untrusted, the switch sets the 802.1p or ToS/DSCP bits in incoming
packets to the default 802.1p or DSCP values configured for that port.
and
commands are used to specify the default 802.1p
and ToS/DSCP values. If no default is specified, then these values are set to zero.
Ports must be
both trusted and configured for 802.1Q
traffic in order to accept 802.1p traffic.
The following applies to ports that are trusted:
•
The 802.1p or ToS/DSCP value is preserved.
•
If the incoming 802.1p or ToS/DSCP flow does not match a policy, the switch places the flow into a
default queue and prioritizes the flow based on the 802.1p or ToS/DSCP value in the flow.
•
If the incoming 802.1p or ToS/DSCP flow matches a policy, the switch queues the flow based on the
policy action.