Configuration Guide User guide

1952 FastIron Configuration Guide
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Rate shaping overview
Rate shaping overview
Outbound Rate Shaping is a port- level feature that is used to shape the rate and control the
bandwidth of outbound traffic on a port. This feature smooths out excess and bursty traffic to the
configured maximum limit before it is sent out on a port. Packets are stored in available buffers
and then forwarded at a rate no greater than the configured limit. This process provides for better
control over the inbound traffic of neighboring devices.
The device has one global rate shaper for a port and one rate shaper for each port priority queue.
Rate shaping is done on a single-token basis, where each token is defined to be 1 byte.
Configuration notes for rate shaping
The following rules apply when configuring outbound rate shapers:
• Outbound rate shapers can be configured only on physical ports, not on virtual or loopback
ports.
• For trunk ports, the rate shaper must be configured on individual ports of a trunk using the
config-trunk-ind command (trunk configuration level); you cannot configure a rate shaper for a
trunk.
• This feature is supported on FastIron X Series and Brocade FCX Series devices only.
• When outbound rate shaping is enabled on a port on an IPv4 device, the port QoS queuing
method (qos mechanism) will be strict mode. This applies to IPv4 devices only. On IPv6
devices, the QoS mechanism is whatever method is configured on the port, even when
outbound rate shaping is enabled.
• You can configure a rate shaper for a port and for the individual priority queues of that port.
However, if a port rate shaper is configured, that value overrides the rate shaper value of a
priority queue if the priority queue rate shaper is greater than the rate shaper for the port.
The configured rate shaper values are rounded up to the nearest multiples of minimum values
supported on the platform. Table 322 shows the minimum and maximum values for output rate
shaping on various devices. Values are in Kbps.
TABLE 322 Output rate shaping on FastIron devices
Device Module Minimum Maximum
ICX 6610 1 Gbps ports 3 999750
ICX 6610 10 Gbps ports 3388 9996513
FCX 1 Gbps ports 89 999666
FCX 10 Gbps ports 3388 9996513
FSX SX-FI48GPP module 51 999485
FSX SX-FI-24GPP module 51 999485
FSX SX-FI424P module 651 999936
FSX SX-FI-2XG module 3 9999000
FSX SX-FI-8XG module 3 9999000