31-2
Configuring System Guard
Configuring System Guard Against IP Attacks
Configuration of System Guard against IP attacks includes these tasks:
z
Enabling System Guard against IP attacks
z
Setting the maximum number of infected hosts that can be concurrently monitored
z
Configuring parameters related to MAC address learning
Follow these steps to configure System Guard against IP attacks:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enable System Guard against IP
attacks
system-guard ip enable
Required
Disabled by default
Set the maximum number of infected
hosts that can be concurrently
monitored
system-guard ip
detect-maxnum
number
Optional
30 by default
Set the maximum number of
addresses that the system can learn,
the maximum number of times an
address can be hit before an action is
taken and the address isolation time
(presented in the number of multiples
of MAC address aging time)
system-guard ip
detect-threshold
ip-record-threshold
record-times-threshold
isolate-time
Optional
By default,
ip-record-threshold
is 30;
record-times-threshold
is 1,
and
isolate-time
is 3.
The correlations among the arguments of the
system-guard ip detect-threshold
command can be
clearly described with this example: If you set
ip-record-threshold
,
record-times-threshold
and
isolate-time
to 30, 1 and 3 respectively, when the system detects successively three times that over 50
IP packets (destined for an address other that an IP address of the switch) from a source IP address are
received within a period of 10 seconds, the system considers that it is being attacked —the system sorts
out the source IP address and decreases the precedence of delivering packets from the source IP
address to the CPU for a period of 5 times the MAC address aging time.
Configuring System Guard Against TCN Attacks
Configuration of System Guard against TCN attacks includes these tasks:
z
Enabling System Guard against TCN attacks
z
Setting the threshold of TCN/TC packet receiving rate
Follow these steps to configure System Guard against TCN attacks:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enable System Guard against
TCN attacks
system-guard tcn enable
Required
Disabled by default