Extreme Networks Summit 300-48, Руководство пользователя программного обеспечения

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Traffic Groupings
Summit 300-48 Switch Software User Guide 127
supports four hardware queues. The transmitting hardware queue determines the bandwidth
management and priority characteristics used when transmitting packets.
To control the mapping of 802.1p prioritization values to hardware queues, 802.1p prioritization values
can be mapped to a QoS profile. The default mapping of each 802.1p priority value to QoS profile is
shown in Table 43.
802.1p Commands
Table 44 shows the command used to configure 802.1p priority. This is explained in more detail in the
following paragraphs.
Configuring 802.1p Priority
When a packet is transmitted by the switch, you can configure the 802.1p priority field that is placed in
the 802.1Q tag. You can configure the priority to be a number between 0 and 7, using the following
command:
config vlan <name> priority <number>
Replacing 802.1p Priority Information
By default, 802.1p priority information is not replaced or manipulated, and the information observed on
ingress is preserved when transmitting the packet. This behavior is not affected by the switching or
routing configuration of the switch.
However, the switch is capable of replacing the 802.1p priority information. To replace 802.1p priority
information, you will use an access list to set the 802.1p value. See Chapter 10, “Access Policies”, for
more information on using access lists. You will use the
set dot1p <dot1p_value>
parameter of the
create access list
command to replace the value. The packet is then placed on the queue that
corresponds to the new 802.1p value.
Table 43: 802.1p Priority Value-to-QoS Profile to Hardware Queue Default Mapping
Priority Value QoS Profile
Hardware Queue
Priority Value
0 Qp1 1
1 Qp2 1
2 Qp3 2
3 Qp4 2
4 Qp5 3
5 Qp6 3
6 Qp7 4
7 Qp8 4
Table 44: 802.1p Configuration Commands
Command Description
config vlan <name> priority <number> Configures the 802.1p priority value for 802.1Q
VLAN tags. The value for
priority
is an
integer between 0 and 7.