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Configuring a single-packet attack protection policy
The single-packet attack protection function determines whether a packet is an attack packet mainly by
analyzing the characteristics of the packet. It is usually applied to interfaces connecting external
networks and inspects only the inbound packets of the interfaces. If detecting an attack packet, the
device outputs an alarm log by default and, depending on your configuration, drops or forwards the
packet.
To configure a policy for preventing single-packet attacks:
To do…
Command…
Remarks
1.
Enter system view.
system-view
—
2.
Enter attack protection policy
view.
attack-defense policy
policy-
number
—
3.
Enable signature detection for
single-packet attacks.
signature-detect
{
fraggle
|
icmp-
redirect
|
icmp-unreachable
|
land
|
large-icmp
|
route-record
|
smurf
|
source-route
|
tcp-flag
|
tracert
|
winnuke
}
enable
Required.
By default, signature detection
is disabled for all kinds of
single-packet attacks.
4.
Configure the ICMP packet
length threshold that triggers
large ICMP attack protection.
signature-detect large-icmp max-
length
length
Optional.
4000 bytes by default.
5.
Configure the device to drop
single-packet attack packets.
signature-detect action drop-
packet
Optional.
By default, the device only
outputs alarm logs if detecting a
single-packet attack.
Configuring a scanning attack protection policy
The scanning attack protection function detects scanning attacks by monitoring the establishment rate of
connections to the target systems. It is usually applied to interfaces connecting external networks and
inspects only the inbound packets of the interfaces. If the device detects that the rate at which an IP
address initiates connections reaches or exceeds the predefined threshold, the device outputs alarm logs,
drops subsequent packets received from the IP address, and, depending on your configuration, adds the
IP address to the blacklist.
To configure a policy for preventing scanning attacks:
To do…
Command…
Remarks
1.
Enter system view.
system-view
—
2.
Enter attack protection policy view.
attack-defense policy
policy-number
—
3.
Enable scanning attack protection.
defense scan enable
Required.
Disabled by default.
4.
Specify the connection rate
threshold that triggers scanning
attack protection.
defense scan max-rate
rate-number
Optional.
4000 connections per second by
default.
5.
Configure
the
blacklist
Enable the blacklist
function for scanning
attack protection.
defense scan add-to-
blacklist
Optional.
Disabled by default.