Command Line Interface
4-182
4
packet filtering will be performed on any untrusted ports within the VLAN as
specified by the
ip dhcp snooping trust
command (page 4-182).
• When the DHCP snooping is globally disabled, DHCP snooping can still be
configured for specific VLANs, but the changes will not take effect until DHCP
snooping is globally re-enabled.
• When DHCP snooping is globally enabled, configuration changes for specific
VLANs have the following effects:
- If DHCP snooping is disabled on a VLAN, all dynamic bindings learned for
this VLAN are removed from the binding table.
Example
This example enables DHCP snooping for VLAN 1.
Related Commands
ip dhcp snooping (4-180)
ip dhcp snooping trust (4-182)
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
• 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.
• Set all ports connected to DHCP servers within the local network or fire wall
to trusted, and all other ports outside the local network or fire wall to untrusted.
• When DHCP snooping ia enabled globally using the
ip dhcp snooping
command (page 4-180), and enabled on a VLAN with
ip dhcp snooping vlan
command (page 4-181), DHCP packet filtering will be performed on any
untrusted ports within the VLAN according to the default status, or as
specifically configured for an interface with the
no ip dhcp snooping trust
command.
• When an untrusted port is changed to a trusted port, all the dynamic DHCP
snooping bindings associated with this port are removed.
Содержание 6152PL2 FICHE
Страница 2: ......
Страница 6: ...vi ...
Страница 8: ...viii ...
Страница 32: ...Tables xxxii ...
Страница 38: ...Figures xxxviii ...
Страница 56: ...Initial Configuration 2 10 2 ...
Страница 378: ...Configuring the Switch 3 322 3 ...
Страница 651: ...Address Table Commands 4 273 4 Example Console show mac address table aging time Aging time 100 sec Console ...
Страница 817: ......
Страница 818: ...SMC6128PL2 SMC6152PL2 149100000007A R01 ...