Cisco CRS Command Reference Manual page 91

Quality of Service Commands on the Cisco IOS XR Software
Default unit for max-threshold and min-threshold is packets.
Command Modes
Policy map class configuration
Command History
Release
Release 2.0
Release 3.2
Release 3.4.0
Release 3.6.0
Release 3.9.0
Release 3.6.0
Usage Guidelines
To use this command, you must be in a user group associated with a task group that includes appropriate task
IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator
for assistance.
WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion
exists. WRED is most useful with protocols like TCP that respond to dropped packets by decreasing the
transmission rate.
Reserved keywords can be specified instead of numeric values. See
on page 45
When the value of the units argument is packets, packets are assumed to be 256 bytes in size.
Task ID
Task ID
qos
Examples The following example shows that for packets with DSCP AF11, the WRED minimum threshold is 1,000,000
bytes and the maximum threshold is 2,000,000 bytes:
RP/0/RP0/CPU0:router(config)# policy-map policy1
OL-23235-03
Modification
This command was introduced.
Range of values for the thresholds changed from 512 to 1073741823 to 0 to
1073741823.
The units argument was added to allow specifying the units of the thresholds.
The dscp-value min-threshold max-threshold arguments were deleted from
the no random-detect dscp command.
Up to eight dscp-values are supported.
For the random-detect dscp command to take effect, there is no longer a
requirement to configure the shape average, bandwidth (QoS), or bandwidth
remaining commands in the user-defined policy map class.
Up to eight dscp-values are supported.
The cells unit was added.
for the list of keywords.
Cisco IOS XR Modular Quality of Service Command Reference for the Cisco CRS Router, Release 4.0
Table 2: IP DSCP Reserved Keywords,
Operations
read, write
random-detect dscp
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