Rate Limiting and Rate Shaping
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Rate Limiting........................................................................................................................................................... 51
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Rate Shaping.......................................................................................................................................................... 61
Rate Limiting
Non ACL-based rate limiting
Port-based fixed rate limiting configuration notes
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Rate limiting is available only on inbound ports.
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We do not support port-based rate limiting for PE ports.
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The rate limit on IPv6 hardware takes several seconds to take effect at higher configured rate limit values. For example, if the
configured rate limit is 750 Mbps, line-rate limiting could take up to 43 seconds to take effect.
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You can enable rate limiting on Static LAG only. You cannot enable rate limiting on other types of LAG.
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You can configure rate limiting on individual ports of the LAG. You cannot configure rate limiting on the LAG itself.
Port-based fixed rate limiting
You can configure a fixed rate limiting policy on a ports inbound direction only. This feature allows you to specify the maximum number of
bytes in kilobits per second (kbps), a given port can receive. The port drops bytes that exceed the limit you specify.
Fixed rate limiting applies to all traffic on the rate limited port. It counts the number of bytes that a port receives in one second intervals. If
the number exceeds the maximum number you specified when you configured the rate, the port drops all further inbound packets for the
duration of the one-second interval. Unused bandwidth is not carried over from one interval to the next. Once the one-second interval is
complete, the port clears the counter and re-enables traffic.
NOTE
Ruckus recommends that you do not use fixed rate limiting on ports that receive route control traffic or Spanning Tree Protocol
(STP) control traffic. If the port drops control packets due to the Fixed rate limiting policy, routing or STP can be disrupted.
When you specify the maximum number of bytes, you specify it in kilobits per second (kbps). The fixed rate limiting policy applies to one-
second intervals and allows the port to receive the number of bytes you specify in the policy, but drops additional bytes. Unused bandwidth
is not carried over from one interval to the next.
Each device supports line-rate rate limiting in hardware. The device creates entries in Content Addressable Memory (CAM) for the rate
limiting policies. CAM entries enable the device to perform the rate limiting in hardware instead of sending the traffic to the CPU. The device
sends the first packet in a given traffic flow to the CPU, which creates a CAM entry for the traffic flow. A CAM entry consists of the source
and destination addresses of the traffic. The device uses the CAM entry for rate limiting all the traffic within the same flow. A rate limiting
CAM entry remains in the CAM for two minutes before aging out.
Ruckus FastIron QoS and Traffic Management Configuration Guide, 08.0.70
Part Number: 53-1005294-01
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