User`s manual

Quality of Service
Command Line
The Switch is already set to automatically read the 802.1p priority bits in incoming packets, map these priorities
to default traffic classes and place priority-tagged packets in traffic class queues for priority servicing.
Important:
You only need to configure QoS settings if you want to change the Switch defaults.
●
By default, the Switch is set to:
read the priority value of all incoming packets and forward across the switching fabric in priority
order
❍
add a priority of 0 to all incoming untagged packets❍
place all outgoing packets in one of four traffic classes based on the packet's priority value❍
●
Configuration commands:
To set the priority of certain traffic over others, set one or more ports:
>set qos trafficclass <port_list> <priority_list> <traffic_class>
maps one or more ports and the priority value of 0-7 to a single traffic class, a value from
0-3. Useful when you have several ports and several priorities to group into a single
traffic class.
<port_list> one or more or a range of ports
<priority_list> a list of one or more priority values, numbers from 0-7
<traffic_class> the transmit priority level; a number from 0-3
Example: >set qos trafficclass 1-12 4-7 3
This example assigns all priority 4,5,6 and 7 traffic from ports 1-12 is to traffc class 3.
1.
To assign your own name to any traffic class:
>set qos trafficclassname <class_list> <class_name>
assigns a name to the specified class or list of classes. For reference only.
<class_list> is the list of traffic classes, numbers from 0-3 assigned to this name
<class_name> is any name you wish to assign to this traffic class
Example: >set qos trafficclassname 3 video
2.
Important: This command applies only to Gigabit ports.
The Switch automatically creates eight inbound queues at each Gigabit port—one for each priority level
The Switch automatically allocates this port memory unless you specify otherwise. Use this command to
make adjustments to the amount of port memory allocated to the eight incoming priority queues. Be very
careful. If queue sizes are set to low, packets will be dropped at the slightest congestion.
>set qos ingressqueuesize <port_list> <priority_list> <percentage>
Gigabit ports only: specifies the amount of port buffer memory available for incoming
packets for specific Gigabit ports and priority values. Incoming queue size cannot be set
on Fast Ethernet ports.
<port_list> one or more or a range of Gigabit ports
<priority_list> one or more or a range of priorities, from 0-7
<percentage> 0 through 100. The default is 100% which means all priorities have
access to all buffer space.
Example: >set qos ingressqueuesize 1-4 2,3,4 50
sets all Priority 2, 3 and 4 queues to 50% for ports 1 through 4
3.
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