D-Link DGS-1250 Emulator - Page 132

ip dhcp snooping limit entries, ip dhcp snooping limit rate

Page 132 highlights

DGS-1250 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide  The router receives a DHCPRELEASE or DHCPDECLINE message from an untrusted host with an entry in the DHCP snooping binding table, and the interface information in the binding table does not match the interface on which the message was received. In addition to doing the validation, DHCP snooping also create a binding entry based on the IP address assigned to client by the server in DHCP snooping binding database. The binding entry contains information including MAC address, IP address, the VLAN ID and port ID where the client is located, and the expiry of the lease time. Example This example shows how to enable DHCP snooping trust for port 3. Switch# configure terminal Switch(config)# interface eth1/0/3 Switch(config-if)# ip dhcp snooping trust Switch(config-if)# 16-9 ip dhcp snooping limit entries This command is used to configure the number of the DHCP snooping binding entries that an interface can learn. Use the no form of this command to reset the DHCP message entry limit. ip dhcp snooping limit entries NUMBER no ip dhcp snooping limit entries Parameters NUMBER Specifies the number of DHCP snooping binding entries limited on a port. The range of value is from 0 to 1024. Default By default, this option is no-limit. Command Mode Interface Configuration Mode. Usage Guideline This command is only available for physical port and port-channel interface configuration. This command only takes effect on untrusted interfaces. The system will stop learning binding entries associated with the port if the maximums number is exceeded. Example This example shows how to configure the limit on binding entries allowed on port 1 to 100. Switch# configure terminal Switch(config)# interface eth1/0/1 Switch(config-if)# ip dhcp snooping limit entries 100 Switch(config-if)# 16-10 ip dhcp snooping limit rate This command is used to configure the number of the DHCP messages that an interface can receive per second. Use the no form of this command to reset the DHCP message rate limiting. 129

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DGS-1250 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide
129
The router receives a DHCPRELEASE or DHCPDECLINE message from an untrusted host with an entry
in the DHCP snooping binding table, and the interface information in the binding table does not match the
interface on which the message was received.
In addition to doing the validation, DHCP snooping also create a binding entry based on the IP address assigned to
client by the server in DHCP snooping binding database. The binding entry contains information including MAC
address, IP address, the VLAN ID and port ID where the client is located, and the expiry of the lease time.
Example
This example shows how to enable DHCP snooping trust for port 3.
Switch# configure terminal
Switch(config)# interface eth1/0/3
Switch(config-if)# ip dhcp snooping trust
Switch(config-if)#
16-9
ip dhcp snooping limit entries
This command is used to configure the number of the DHCP snooping binding entries that an interface can learn.
Use the
no
form of this command to reset the DHCP message entry limit.
ip dhcp snooping limit entries
NUMBER
no ip dhcp snooping limit entries
Parameters
NUMBER
Specifies the number of DHCP snooping binding entries limited on a port. The
range of value is from 0 to 1024.
Default
By default, this option is no-limit.
Command Mode
Interface Configuration Mode.
Usage Guideline
This command is only available for physical port and port-channel interface configuration. This command only
takes effect on untrusted interfaces. The system will stop learning binding entries associated with the port if the
maximums number is exceeded.
Example
This example shows how to configure the limit on binding entries allowed on port 1 to 100.
Switch# configure terminal
Switch(config)# interface eth1/0/1
Switch(config-if)# ip dhcp snooping limit entries 100
Switch(config-if)#
16-10
ip dhcp snooping limit rate
This command is used to configure the number of the DHCP messages that an interface can receive per second.
Use the
no
form of this command to reset the DHCP message rate limiting.