3com 5500-ei pwr Installation Instruction
5-2
To do…
Use the command…
Remarks
Enter port view
interface interface-type
interface-number
interface-number
—
Enable the DHCP packet
rate limit function
rate limit function
dhcp rate-limit enable
Required
By default, DHCP packet rate limit is
disabled.
disabled.
Configure the maximum
DHCP packet rate allowed
on the port
DHCP packet rate allowed
on the port
dhcp rate-limit rate
Optional
By default, the maximum rate is 15
pps.
pps.
Enable the port state
auto-recovery function
auto-recovery function
dhcp protective-down
recover enable
recover enable
Optional
By default, the port state
auto-recovery function is disabled.
auto-recovery function is disabled.
Set the port state
auto-recovery interval
auto-recovery interval
dhcp protective-down
recover interval interval
recover interval interval
Optional
The port state auto-recovery interval
is 300 seconds.
is 300 seconds.
z
Enable the port state auto-recovery function before setting the auto-recovery interval.
z
You are not recommended to configure DHCP packet rate limit on the ports of an aggregation
group.
Configuring Port State Auto Recovery
Follow these steps to configure port state auto recovery:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enable port state auto-recovery
dhcp protective-down
recover enable
recover enable
Required
By default, this function is
disabled.
disabled.
Configure the port state
auto-recovery interval
auto-recovery interval
dhcp protective-down
recover interval interval
recover interval interval
Optional
By default, the auto-discovery
interval is 300 seconds.
interval is 300 seconds.
Rate Limit Configuration Example
Network requirements
As shown in
, Ethernet 1/0/1 of the S5500-EI switch is connected to the DHCP server.
Ethernet 1/0/2 is connected to client B and Ethernet 1/0/11 is connected to client A.
z
Enable DHCP snooping on the switch, and specify Ethernet 1/0/1 as the DHCP snooping trusted
port.