Tripp Lite NGI-M08C4POE8-2 Owner's Manual page 236

The DHCP server connected to an un-trusted port will be filtered.
Notices:
There are a global state and per VLAN states.
When the global state is disabled, the DHCP Snooping on the Switch is disabled even per
VLAN states are enabled.
When the global state is enabled, user must enable per VLAN states to enable the DHCP
Snooping on the specific VLAN.
VLAN 1 : port 1-4.
DHCP Client-1 : connect to port 3.
DHCP Server : connect to port 1.
Procedures:
1. Default environments:
A. DHCP Client-1: ipconfig /release
B. DHCP Client-1: ipconfig /renew
 DHCP Client-1 can get an IP address.
2. Enable the global DHCP Snooping.
A. L2SWITCH(config)#dhcp-snooping
B. DHCP Client-1: ipconfig /release
C. DHCP Client-1: ipconfig /renew
 DHCP Client-1 can get an IP address.
3. Enable the global DHCP Snooping and VLAN 1 DHCP Snooping.
A. L2SWITCH(config)#dhcp-snooping
B. L2SWITCH(config)#dhcp-snooping vlan 1
C. DHCP Client-1: ipconfig /release
D. DHCP Client-1: ipconfig /renew
 DHCP Client-1 cannot get an IP address.
; Because the DHCP server connects to a un-trust port.
4. Enable the global DHCP Snooping and VLAN 1 DHCP Snooping.
A. L2SWITCH(config)#dhcp-snooping
B. L2SWITCH(config)#dhcp-snooping vlan 1
C. L2SWITCH(config)#interface gi1/0/1
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