Brocade Communications Systems Brocate Ethernet Access Switch 6910 - Manual (Page 271)

Brocade 6910 Ethernet Access Switch Configuration Guide 221
53-1002581-01
DHCP Snooping
10
Default Setting
Disabled
Command Mode
Global Configuration
Command Usage
• When DHCP snooping enabled globally using the ip dhcp snooping command, and enabled on
a VLAN with this command, DHCP packet filtering will be performed on any untrusted ports
within the VLAN as specified by the
ip dhcp snooping trust command.
• 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, and DHCP snooping is then disabled on a specific
VLAN, all dynamic bindings learned for this VLAN are removed from the binding table.
Example
This example enables DHCP snooping for VLAN 1.
Console(config)#ip dhcp snooping vlan 1
Console(config)#
Related Commands
ip dhcp snooping (216)
ip dhcp snooping trust (222)
ip dhcp snooping information option circuit-id
This command enables the use of DHCP Option 82 information circuit-id suboption. Use the no
form to disable this feature.
Syntax
ip dhcp snooping information option circuit-id string string
no dhcp snooping information option circuit-id
string - An arbitrary string inserted into the circuit identifier field. (Range: 1-32 characters)
Default Setting
Disabled
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• DHCP provides a relay mechanism for sending information about the switch and its DHCP
clients to the DHCP server. DHCP Option 82 allows compatible DHCP servers to use the
information when assigning IP addresses, to set other services or policies for clients. For more
information of this process, refer to the Command Usage section under the
ip dhcp snooping
information option command.