Need help understanding why I need dhcp snooping trust on my access interface when using ip helper?

dpwtheitguydpwtheitguy Member Posts: 1 ■■□□□□□□□□

Hope everyone is doing well. Looking a dhcp snooping for today's topic. Basically I have a DHCP server in another subnet and when I enable dhcp snooping I expected that I would only have to enable trust ports in two place lanswitch's interface facing the router and dcswitch's interface facing the dhcp server.

However when I lab this topology I end up needing to put trust on all interfaces in the process.

dhcpclient >> (e1) lanswitch (e0) >> Router << dcswitch << dhcpserver

My understanding is that snooping only happens on data coming into a port and only applies to offer and accept traffic coming from the DHCP server. Which doesn't juve with my lab where I have to apply a trust to the lanswitch's interface serving dhclient (e1). 

Any one clarify where I might being going wrong? Or help me better understand the snooping process as it pretains to being relayed by the DHCP helper? 


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