Juniper E320 User Manual

Hierarchical Rate Limits ! 87
Chapter 3: Creating Rate-Limit Profiles
host1(config)#policy-list TOS1_oversubsribed
host1(config-policy-list)#classifier-group A parent-group S
host1(config-policy-list-classifier-group)#rate-limit-profile indiv
host1(config-policy-list-classifier-group)#mark profile A
host1(config--classifier-group)#exit
host1(config-policy-list)#classifier-group B parent-group S
host1(config-policy-list-classifier-group)#rate-limit-profile indiv
host1(config-policy-list-classifier-group)#mark profile BC
host1(config--classifier-group)#exit
host1(config-policy-list)#classifier-group C parent-group S
host1(config-policy-list-classifier-group)#rate-limit-profile indiv
host1(config-policy-list-classifier-group)#mark profile BC
host1(config-policy-list-classifier-group)#exit
host1(config-policy-list)#parent-group S
host1(config-policy-list-parent-group)#rate-limit-profile S
host1(config-policy-list-parent-group)#exit
Color-Aware Configuration
Common to many rate-limit hierarchies is a large aggregate rate limit that receives
packets from many smaller individual rate limits. An individual rate limit can mark
a packet yellow but, if few individual flows are active, the aggregate rate limit is
likely to try to promote it to green, overriding the individual rate limit. For this
reason, rate limits never promote packets in color; color-aware rate limits use the
incoming color in their algorithm, but the final result is always equal to or less than
the initial packet color.
Rate-limit profiles for rate-limit hierarchies include a non-default configuration
option for color-aware. For two-rate rate limits this option enables the color-aware
algorithm. If hierarchical, TCP-friendly one-rate rate limits have a color-aware
algorithm defined.
In the following color-aware example, the non-preferred packets do not take any
green tokens from rate-limit A, leaving them all for preferred packets. Preferred
packets may take green and also take yellow tokens (which reduces the flow of
non-preferred). In this way the non-preferred packets do not reduce the number of
green preferred packets, only the number of yellow preferred packets; preferred
packets are then marked from a color-mark profile.
class non-preferred parent A
color yellow
class preferred parent A
mark profile cm
parent A
rate-limit A !! a color-aware rate limit
The color-mark profile translates the packet color, which is independent of its type,
to a type-dependent mark for ToS or EXP and applies it to a packet after it has
exited the rate-limit hierarchy. If no translation is configured for a color, then
packets of that color are not changed.

Juniper E320 Specifications

General

Brand	Juniper
Model	E320
Category	Network Router
Language	English