D-Link DGS-1250 Emulator - Page 127
DHCP Snooping Commands
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DGS-1250 Series Gigabit Ethernet Smart Managed Switch CLI Reference Guide 16. DHCP Snooping Commands 16-1 ip dhcp snooping This command is used to globally enable DHCP snooping. Use the no form of this command to disable DHCP snooping. ip dhcp snooping no ip dhcp snooping Parameters None. Default By default, this option is disabled. Command Mode Global Configuration Mode. Usage Guideline The DHCP snooping function snoops the DHCP packets arriving at the untrusted interface on the VLAN that is enabled for DHCP snooping. With this function, the DHCP packets that come from the untrusted interface can be validated and a DHCP binding database will be constructed for the DHCP snooping enabled VLAN. The binding database provides IP and MAC binding information that can be further used by the IP source guard and dynamic ARP inspection process. Example This example shows how to enable DHCP snooping. Switch# configure terminal Switch(config)# ip dhcp snooping Switch(config)# 16-2 ip dhcp snooping information option allow-untrusted This command is used to globally allow DHCP packets with the relay Option 82 on the untrusted interface. Use the no form of this command to not allow packets with the relay Option 82. ip dhcp snooping information option allow-untrusted no ip dhcp snooping information option allow-untrusted Parameters None. Default By default, this option is not allowed. Command Mode Global Configuration Mode. 124
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