Cisco IE 4000, Software Configuration Manual

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Configuring DHCP
How to Configure DHCP
Enabling the DHCP Snooping Binding Database Agent
8. ip dhcp snooping vlan vlan information
option format-type circuit-id
[override] string
ASCII-string
(Optional) Configures the circuit-ID suboption for the specified interface.
Specifies the VLAN and port identifier, using a VLAN ID in the range of
1 to 4096. The default circuit ID is the port identifier in the format
vlan-mod-port.
You can configure the circuit ID to be a string of 3 to 63 ASCII characters
(no spaces).
(Optional) Use the override keyword when you do not want the circuit-ID
suboption inserted in TLV format to define subscriber information.
9. ip dhcp snooping trust (Optional) Configures the interface as trusted or as untrusted. Use the no
keyword to configure an interface to receive messages from an untrusted
client. The default setting is untrusted.
10. ip dhcp snooping limit rate rate (Optional) Configures the number of DHCP packets per second that an
interface can receive. The range is 1 to 2048. By default, no rate limit is
configured.
Note: We recommend an untrusted rate limit of not more than 100
packets per second. If you configure rate limiting for trusted interfaces,
you might need to increase the rate limit if the port is a trunk port
assigned to more than one VLAN with DHCP snooping.
11. exit Returns to global configuration mode.
12. ip dhcp snooping verify mac-address (Optional) Configures the switch to verify that the source MAC address in
a DHCP packet received on untrusted ports matches the client hardware
address in the packet. The default is to verify that the source MAC
address matches the client hardware address in the packet.
13. end Returns to privileged EXEC mode.
Command Purpose
Command Purpose
1. configure terminal Enters global configuration mode.
2. ip dhcp snooping database
{ flash:/ filename |
ftp:// user : password@host / filename |
http:// [[ username : password ]@]{ hostna
me | host-ip }[/ directory ]
/ image-name .tar |
rcp:// user@host / filename }|
tftp:// host / filename
Specifies the URL for the database agent or the binding file by using one
of these forms:

flash:/ filename

ftp:// user : password @ host / filename

http:// [[ username : password ]@]{ hostname | host-ip }[/ directory ]
/ image-name .tar

rcp:// user @ host / filename

tftp:// host / filename
3. ip dhcp snooping database timeout
seconds
Specifies (in seconds) how long to wait for the database transfer process
to finish before stopping the process.
The default is 300 seconds. The range is 0 to 86400. Use 0 to define an
infinite duration, which means to continue trying the transfer indefinitely.