3Com 8800 Configuration Manual page 394

3Com Switch 8800 Configuration Guide
After receiving a packet, the switch allocates a set of service parameters to it according
to a specific rule. The switch first gets its local precedence and drop precedence
according to the packet 802.1p priority value, by searching in the CoS — >
Local-precedence mapping table and the CoS —> Drop-precedence mapping table.
Default values are available for the two mapping tables, but you can also configure the
mapping tables according to your needs. If the switch fails in allocating local
precedence for the packet, it configures the local precedence of the packet to be the
precedence of the port that receives this packet. After obtaining the packet CoS value
by inverse-searching the CoS —> Local-precedence mapping table, the switch then
gets its drop precedence from the CoS —> Drop-precedence mapping table.
I. Configuring mapping table
Perform the following configurations in system view.
Table 33-3 Configure mapping tables
Configure
Drop-precedence mapping table
Restore the default values of CoS —>
Drop-precedence mapping table
Configure
Local-precedence mapping table
Restore the default values of CoS —>
Local-precedence mapping table
By default, the switch obtains local precedence and drop precedence according to the
default mapping values.
II. Configuring default local precedence for port
Perform the following configurations in Ethernet port view or port group view.
Operation
—
the CoS
—
the CoS
33-10
Chapter 33 QoS Configuration
Command
qos cos-drop-precedence-map
cos0-map-drop-prec
cos1-map-drop-prec
cos2-map-drop-prec
>
cos3-map-drop-prec
cos4-map-drop-prec
cos5-map-drop-prec
cos6-map-drop-prec
cos7-map-drop-prec
undo qos cos-drop-precedence-map
qos cos-local-precedence-map
cos0-map-local-prec
cos1-map-local-prec
cos2-map-local-prec
>
cos3-map-local-prec
cos4-map-local-prec
cos5-map-local-prec
cos6-map-local-prec
cos7-map-local-prec
undo qos cos-local-precedence-map