R3303-HP HSR6800 Routers Security Command Reference

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Default
No ICMP flood attack protection thresholds are configured for an IP address.
Views
Attack protection policy view
Default command level
2: System level
Parameters
ip-address: IP address to be protected. This IP address cannot be a broadcast address, 127.0.0.0/8, a
class D address, or a class E address.
high rate-number: Sets the action threshold for ICMP flood attack protection of the specified IP address.
The rate-number argument indicates the number of ICMP packets sent to the specified IP address per
second and is in the range of 1 to 64000. With the ICMP flood attack protection enabled, the device
enters attack detection state. When the device detects that the sending rate of ICMP packets destined for
the specified IP address constantly reaches or exceeds the specified action threshold, the device
considers the IP address to be under attack, enters attack protection state, and takes protection actions
as configured.
low rate-number: Sets the silence threshold for ICMP flood attack protection of the specified IP address.
The rate-number argument indicates the number of ICMP packets sent to the specified IP address per
second and is in the range of 1 to 64000. The default value of the silence threshold is 3/4 of the action
threshold. When the device is in attack protection state, if it detects that the sending rate of ICMP packets
destined for the specified IP address drops below the silence threshold, it considers that the attack is over,
returns to attack detection state, and stops the protection actions.
Usage guidelines
You can configure ICMP flood attack protection thresholds for a maximum of 32 IP addresses in an attack
protection policy.
Examples
# Enable ICMP flood attack protection for IP address 192.168.1.2, and set the action threshold to 2000
packets per second and the silence threshold to 1000 packets per second.
<Sysname> system-view
[Sysname] attack-defense policy 1
[Sysname-attack-defense-policy-1] defense icmp-flood ip 192.168.1.2 rate-threshold high
2000 low 1000
Related commands
• defense icmp-flood action drop-packet
• defense icmp-flood enable
• display attack-defense policy
defense icmp-flood rate-threshold
Use defense icmp-flood rate-threshold to configure the global action and silence thresholds for ICMP
flood attack protection. The device uses the global attack protection thresholds to protect IP addresses for
which you do not configure attack protection parameters specifically.
Use undo defense icmp-flood rate-threshold to restore the default.