Brocade FastIron Ethernet Switch Traffic Management Guide - Manual (Page 49)

(packets in ICX 6650) in each interval. However, the port receives more than 500000 bits (packets in
ICX 6650) during the third and fourth one-second intervals, and consequently drops the excess traffic.
FIGURE 5 Fixed rate limiting
NOTE
The software counts the bytes (packets in ICX 6650) by polling statistics counters for the port every 100
milliseconds, which provides 10 readings each second. Due to the polling interval, the Fixed Rate
Limiting policy has an accuracy of within 10% of the port's line rate. It is therefore possible for the policy
to sometimes allow more traffic than the limit you specify, but the extra traffic is never more than 10% of
the port's line rate.
Configuration notes for rate limiting
• Rate limiting is available only on inbound ports.
• Port based Rate limiting is not supported on the SX-FI62XG and SX-FI42XG modules of the
FastIron X Series devices.
• FastIron X Series devices do not support fixed rate limiting on tagged ports in the base Layer 3 and
full Layer 3 images.
• 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 (1500000 packets/second, in ICX
6650), line-rate limiting could take up to 43 seconds to take effect.
• You can enable rate limiting on Static LAG only. You cannot enable rate limiting on other types of
LAG.
• You can configure rate limiting on individual ports of the LAG. You cannot configure rate limiting on
the LAG itself.
Configuration notes for rate limiting
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