Chapter 32
Configuring PFC QoS
Note
To avoid out-of-sequence packets, configure the markdown maps so that conforming and
•
nonconforming traffic uses the same queue.
You can enter up to 8 DSCP values that map to a marked-down DSCP value.
•
You can enter multiple commands to map additional DSCP values to a marked-down DSCP value.
•
You can enter a separate command for each marked-down DSCP value.
•
Note
Configure marked-down DSCP values that map to CoS values consistent with the markdown penalty (see
the
"Mapping Internal DSCP Values to Egress CoS Values" section on page
This example shows how to map DSCP 1 to marked-down DSCP value 0:
Router# configure terminal
Enter configuration commands, one per line.
Router(config)# mls qos map policed-dscp normal-burst 1 to 0
Router(config)# end
This example shows how to verify the configuration:
Router# show mls qos map
Normal Burst Policed-dscp map:
Maximum Burst Policed-dscp map:
<...Output Truncated...>
Router#
Note
In the Policed-dscp displays, the marked-down DSCP values are shown in the body of the matrix; the
first digit of the original DSCP value is in the column labeled d1 and the second digit is in the top row.
In the example shown, DSCP 41 maps to DSCP 41.
78-14064-04
When you create a policer that does not use the pir keyword, and the maximum_burst_bytes
parameter is equal to the normal_burst_bytes parameter (which occurs if you do not enter
the maximum_burst_bytes parameter), the exceed-action policed-dscp-transmit keywords
cause PFC QoS to mark traffic down as defined by the policed-dscp max-burst markdown
map.
d1 :
d2 0
1
2
3
4
-------------------------------------
0 :
00 01 02 03 04 05 06 07 08 09
1 :
10 11 12 13 14 15 16 17 18 19
2 :
20 21 22 23 24 25 26 27 28 29
3 :
30 31 32 33 34 35 36 37 38 39
4 :
40 41 42 43 44 45 46 47 48 49
5 :
50 51 52 53 54 55 56 57 58 59
6 :
60 61 62 63
d1 :
d2 0
1
2
3
4
-------------------------------------
0 :
00 01 02 03 04 05 06 07 08 09
1 :
10 11 12 13 14 15 16 17 18 19
2 :
20 21 22 23 24 25 26 27 28 29
3 :
30 31 32 33 34 35 36 37 38 39
4 :
40 41 42 43 44 45 46 47 48 49
5 :
50 51 52 53 54 55 56 57 58 59
6 :
60 61 62 63
End with CNTL/Z.
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Cisco 7600 Series Router Cisco IOS Software Configuration Guide—12.1E
Configuring PFC QoS
32-67).
(dscp= d1d2)
(dscp= d1d2)
32-69