Supermicro SSE-G2252, Руководство пользователя

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Chapter 37: Class of Service Commands
Priority Commands (Layer 3 and 4)
– 1127 –
C
OMMAND
U
SAGE
•
The default mapping of CoS to PHB values shown in Table 37-4 is based
on the recommended settings in IEEE 802.1p for mapping CoS values
to output queues.
•
Enter a value pair for the internal per-hop behavior and drop
precedence, followed by the keyword “from” and then up to eight CoS/
CFI paired values separated by spaces.
•
If a packet arrives with a 802.1Q header but it is not an IP packet, then
the CoS/CFI-to-PHB/Drop Precedence mapping table is used to
generate priority and drop precedence values for internal processing.
Note that priority tags in the original packet are not modified by this
command.
•
The internal DSCP consists of three bits for per-hop behavior (PHB)
which determines the queue to which a packet is sent; and two bits for
drop precedence (namely color) which is used by Random Early
Detection (RED) to control traffic congestion.
•
The specified mapping applies to all interfaces.
E
XAMPLE
Console(config)#qos map cos-dscp 0 0 from 0 1
Console(config)#
qos map
dscp-mutation
This command maps DSCP values in incoming packets to per-hop behavior
and drop precedence values for priority processing. Use the no form to
restore the default settings.
S
YNTAX
qos map dscp-mutation phb drop-precedence from dscp0 ... dscp7
no qos map dscp-mutation dscp0 ... dscp7
phb - Per-hop behavior, or the priority used for this router hop.
(Range: 0-7)
drop-precedence - Drop precedence used in controlling traffic
congestion.
(Range: 0 - Green, 3 - Yellow, 1 - Red)
dscp - DSCP value in ingress packets. (Range: 0-63)
D
EFAULT
S
ETTING
.
Table 37-5: Default Mapping of DSCP Values to Internal PHB/Drop Values
ingress-
dscp1
ingress-
dscp10
0 1 2 3 4 5 6 7 8 9
0 0,0 0,1 0,0 0,3 0,0 0,1 0,0 0,3 1,0 1,1
1 1,0 1,3 1,0 1,1 1,0 1,3 2,0 2,1 2,0 2,3