TP-Link TL-SG5426 -, Installation Manual

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Command Line Interface
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identified by the switch port to which they are connected rather than just their
MAC address. DHCP client-server exchange messages are then forwarded
directly between the server and client without having to flood them to the
entire VLAN.
• DHCP snooping must be enabled on the switch for the DHCP Option 82
information to be inserted into packets.
Example
This example enables the DHCP Snooping Information Option.
ip dhcp snooping information policy
This command sets the DHCP snooping information option policy for DHCP client
packets that include Option 82 information.
Syntax
ip dhcp snooping information policy < drop | keep | replace >
• drop - Discards the Option 82 information in a packet and then floods it to
the entire VLAN.
• keep - Retains the client’s DHCP information
• replace - Overwrites the DHCP client packet information with the switch’s
relay information.
Default Setting
replace
Command Mode
Global Configuration
Command Usage
When the switch receives DHCP packets from clients that already include
DHCP Option 82 information, the switch can be configured to set the action
policy for these packets. Either the switch can drop the DHCP packets, keep
the existing information, or replace it with the switch’s relay information.
Example
Console(config)#ip dhcp snooping information option
Console(config)#
Console(config)#ip dhcp snooping information policy drop
Console(config)#