Ip Dhcp Snooping Trust - Edge-Core ECS2100-10T Reference Manual

ip dhcp snooping trust

access node identifier - ASCII string. Default is the MAC address of the
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switch's CPU. This field is set by the
command,
eth - The second field is the fixed string "eth"
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slot - The slot represents the stack unit for this system.
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port - The port which received the DHCP request. If the packet arrives over
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a trunk, the value is the ifIndex of the trunk.
vlan - Tag of the VLAN which received the DHCP request.
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Note that the sub-type and sub-length fields can be enabled or disabled
using the ip dhcp snooping information option
The ip dhcp snooping information option circuit-id command can be
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used to modify the default settings described above.
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The format for TR101 option 82 is: "<IP> eth <SID>/<PORT>[:<VLAN>]". Note
that the SID (Switch ID) is always 0. By default the PVID is added to the end of
the TR101 field for untagged packets. For tagged packets, the VLAN ID is always
added. Use the ip dhcp snooping information option remote-id tr101 no-
vlan-field command to remove the VLAN ID from the end of the TR101 field for
untagged packets. Use the no form of this command to add the PVID for
untagged packets at the end of the TR101 field.
Example
This example sets the DHCP Snooping Information circuit-id suboption string.
Console(config)#interface ethernet 1/1
Console(config-if)#ip dhcp snooping information option circuit-id string 4500
Console(config-if)#
This command configures the specified interface as trusted. Use the no form to
restore the default setting.
Syntax
[no] ip dhcp snooping trust
Default Setting
All interfaces are untrusted
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
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A trusted interface is an interface that is configured to receive only messages
from within the network. An untrusted interface is an interface that is
configured to receive messages from outside the network or fire wall.
Chapter 9
ip dhcp snooping information option
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| General Security Measures
DHCPv4 Snooping
command.