Reference v4.1.0 Instruction Manual

Network OS Command Reference 353

53-1003115-01

ip icmp rate-limit

Limits the rate at which Internet Control Message Protool (ICMP) messages are sent on an IPv4

network.

Synopsis ip icmp rate-limit milliseconds

no ip icmp rate-limit

Operand milliseconds Number of milliseconds between packets. The range is from 1 through

4294967295.

Defaults The default value is 1000 milliseconds.

Command Modes Interface configuration mode

Description This command limits the rate at which ICMP messages are sent on an IPv4 network. To protect

against TCP SYN attacks, you can configure the Brocade device to drop TCP SYN packets when

excessive numbers of messages are encountered. You can set threshold values for TCP SYN

packets that are targeted at the router itself or passing through an interface, and drop them when

the thresholds are exceeded.

Usage Guidelines The configuration is persistent across a switch reload. Once it is enabled, all outbound ICMP

message types are rate limited.

Examples None