One way ip dhcp snooping at switch

[Leftz]

Hi we have switches connection like this:  dhcp server -----(g0/3)switch1(g0/1) ------(g0/2)switch2(g0/4)-----client

You can see four interfaces are labeled in the diagram above. If we want to add ip dhcp snooping trust, the command have to be added to all of the four interfaces? or just g0/1 and g0/4? Thank you

[Jaderson Pessoa · Accepted solution]

the dhcp snooping trust must be used on trunks interfaces (between switches) and where is the dhcp server.

look this guide: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/snoodhcp.html

[Leftz]

Hi Jaderson. Thank you for your reply!

I got the below output:

SwitchABC#sh ip dhcp snooping
Switch DHCP snooping is disabled
Switch DHCP gleaning is disabled
DHCP snooping is configured on following VLANs:
10,20
DHCP snooping is operational on following VLANs:
10,20

Do you think the snooping is working at the switch? if yes, but it shows "snooping is disabled"

[Jaderson Pessoa · Accepted solution]

it is not working, it says vlan has the command "ip dhcp snooping" under it. 

by the way: configure terminal: ip dhcp snooping (will enable it globally)

ps: map you interfaces and vlans that will participate of dhcp snooping.

check the guide i've sent to you, there is a logic configuration to implement it.

 https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6500/ios/12-2SX/configuration/guide/book/snoodhcp.html