IP Configuration
IPv4 Management and Interfaces
288 Cisco Small Business 200, 300 and 500 Series Managed Switch Administration Guide (Internal Version) 
17
DHCP Snooping Along With DHCP Relay
If both DHCP Snooping and DHCP Relay are globally enabled, then if DHCP 
Snooping is enabled on the client's VLAN, DHCP Snooping rules contained in the 
DHCP Snooping Binding database are applied, and the DHCP Snooping Binding 
database is updated in the client's and DHCP server’s VLAN, for packets that are 
relayed. 
DHCP Default Configuration
The following describes DHCP Snooping and DHCP Relay default options.
DHCP Default Options
Configuring DHCP Work Flow
To configure DHCP Relay and DHCP Snooping:
DHCPRELEASE Same as 
DHCPDECLINE.
Same as DHCPDECLINE.
DHCPINFORM Forward to trusted 
interfaces only.
Forward to trusted interfaces 
only.
DHCPLEASEQUE
RY
Filtered. Forward.
Packet Type Arriving from 
Untrusted Ingress 
Interface
Arriving from Trusted Ingress 
Interface
Option Default State
DHCP Snooping Enabled
Option 82 Insertion Not enabled
Option 82 Passthrough Not enabled
Verify MAC Address Enabled
Backup DHCP Snooping 
Binding Database
Not enabled
DHCP Relay Disabled