H3C MSR Series Command Reference

1081
syn-ack-flood action
Use syn-ack-flood action to specify global actions against SYN-ACK flood attacks.
Use undo syn-ack-flood action to restore the default.
Syntax
syn-ack-flood action { client-verify | drop | logging } *
undo syn-ack-flood action
Default
No global action is specified for SYN-ACK flood attacks.
Views
Attack defense policy view
Predefined user roles
network-admin
Parameters
client-verify: Adds the victim IP addresses to the protected IP list for TCP client verification. If TCP
client verification is enabled, the device provides proxy services for protected servers.
drop: Drops subsequent SYN-ACK packets destined for the victim IP addresses.
logging: Enables logging for SYN-ACK flood attack events.
Usage guidelines
For the SYN-ACK flood attack detection to collaborate with the TCP client verification, make sure the
client-verify keyword is specified and the TCP client verification is enabled. To enable TCP client
verification, use the client-verify tcp enable command.
Examples
# Specify drop as the global action against SYN-ACK flood attacks in the attack defense policy
atk-policy-1.
<Sysname> system-view
[Sysname] attack-defense policy atk-policy-1
[Sysname-attack-defense-policy-atk-policy-1] syn-ack-flood action drop
Related commands
client-verify tcp enable
syn-ack-flood detect
syn-ack-flood detect non-specific
syn-ack-flood threshold
syn-ack-flood detect
Use syn-ack-flood detect to configure IP address-specific SYN-ACK flood attack detection.
Use undo syn-ack-flood detect to remove the IP address-specific SYN-ACK flood attack detection
configuration.
Syntax
syn-ack-flood detect { ip ipv4-address | ipv6 ipv6-address } [ vpn-instance vpn-instance-name ]
[ threshold threshold-value ] [ action { { client-verify | drop | logging } * | none } ]

H3C MSR Series Specifications

General

Category	Network Router
IPv6 Support	Yes
Dimensions	Varies by model
Weight	Varies by model
Product Type	Modular Router
Ports	Varies by model
WAN Interfaces	Varies by model
Firewall	Yes
QoS	Yes
Wireless Support	Varies by model
USB Ports	Varies by model
Console Port	Yes
Power Supply	Varies by model
Redundancy	Varies by model
Operating Temperature	0°C to 45°C
Storage Temperature	-40°C to 70°C
Humidity	5% to 95% non-condensing
Series	MSR
Certifications	CE, FCC, RoHS