655
Views
Attack defense policy view
Predefined user roles
network-admin
Usage guidelines
This command enables global SYN flood attack detection. It applies to all IP addresses except for those
specified by the syn-flood detect command. The system uses the global trigger threshold set by the
syn-flood threshold command and global actions specified by the syn-flood action command.
Examples
# Enable SYN flood attack detection for non-specific IP addresses in attack defense policy atk-policy-1.
<Sysname> system-view
[Sysname] attack-defense policy atk-policy-1
[Sysname-attack-defense-policy-atk-policy-1] syn-flood detect non-specific
Related commands
• syn-flood action
• syn-flood detect
• syn-flood threshold
syn-flood threshold
Use syn-flood threshold to set the global threshold for triggering SYN flood attack prevention.
Use undo syn-flood threshold to restore the default.
Syntax
syn-flood threshold threshold-value
undo syn-flood threshold
Default
The global threshold is 1000 for triggering SYN flood attack prevention.
Views
Attack defense policy view
Predefined user roles
network-admin
Parameters
threshold-value: Specifies the threshold for triggering SYN flood attack prevention. The value range is 1
to 1000000 in units of SYN packets sent to an IP address per second.
Usage guidelines
The global threshold applies to SYN flood attack detection for non-specific IP addresses.
Adjust the threshold according to the application scenarios. If the number of SYN packets to a protected
server, such as an HTTP or FTP server, is normally large, set a large threshold. A small threshold might
affect the server services. For a network that is unstable or susceptible to attacks, set a small threshold.