egress-quantization
Syntax
egress-quantization
Hierarchy Level
[edit forwarding-options enhanced-hash-key ecmp-dlb]
Description
Selective dynamic load balancing selects an optimal link based on:
-
Port load metric - Amount of traffic in bytes transmitted in recent past over each ECMP link.
-
Port queue metric - Amount of traffic in number of cells enqueued on each ECMP link for transmission.
Use egress-quantization
to configure the desired ratio of port
load metric to port queue metric based on the traffic pattern. Member link
quality is quantized in the range of 0 to 7. A link quality value of 0
indicates the worst quality link whereas a value of 7 indicates a best
quality link. Quantization levels can be configured by setting minimum and
maximum thresholds along with rate-weightage.
Rate-weightage is the ratio of port load metric to port queue metric. Assume rate-weightage is configured as 60%. Then a link is chosen amongst competing links if the link has a higher port load metric than its port queue metric.
Minimum threshold is the minimum bandwidth threshold level of the total link bandwidth. When bandwidth level drops below this level, the device assigns this link with a best quality band value (value 7). Assume the value set is 20. When the ECMP link transmits traffic lower than 20% of link bandwidth, the device assigns a best quality band value to this link.
Maximum threshold is the maximum bandwidth threshold level of the total link bandwidth. When bandwidth level rises above this level, the device assigns this link with a worst quality band value (value 0). Assume the value is set to 80. When the ECMP link transmits traffic higher than 80% of the link bandwidth, the device assigns worst quality band value to this link.
The following table summarizes egress quantization link quality values.
Egress quantization when egress rate weightage is configured with value of 100% |
|
---|---|
Egress Link Bandwidth utilization |
Quality Band |
Lesser than 20 |
7 (Best) |
21-30 |
6 |
31-40 |
5 |
41-50 |
4 |
51-60 |
3 |
61-70 |
2 |
71-80 |
1 |
Greater than 80 |
0 (Worst) |
Default
When selective dynamic load balancing is configured, the default ratio of port load metric to port queue rate weightage is 50:50 for per-packet mode and flowlet-mode. The default values of minimum threshold value and maximum threshold value are:
Per-packet mode
-
EgressBytes Min Threshold - 80
-
EgressBytes Max Threshold - 99
Flowlet mode
-
EgressBytes Min Threshold - 20
-
EgressBytes Max Threshold - 50
Options
-
apply-groups
-
max
-
min
-
rate-weightage
Required Privilege Level
interface—To view this statement in the configuration.
interface-control—To add this statement to the configuration.
Release Information
Statement introduced in Junos OS Evolved Release 24.1