I have a problem when enabling DHCP snooping, all the clients get dropped from the switch when I disable it they work just fine. I am using version 16.10.01 on C9407R switch, does anyone have a similar issue or this is a bug and how to solve it.
I appreciate your feedbacks.
Could you please provide switch configuration?
I've checked release note and I've seen issue relative to IP source guard (CSCvn04524) but not with DHCP snooping.
Do you configure port connected to DHCP server (or the uplink port / port-channel) with "ip dhcp snooping trust"?
find below configuration:
ip dhcp snooping vlan 1-4094
no ip dhcp snooping information option
ip dhcp snooping
description Link vs ROUTER 2
switchport access vlan 15
switchport mode access
service-policy input POLICY_FILESYSTEM_INBOUND
service-policy output POLICY_FILESYSTEM
ip dhcp snooping trust
Now the command "IP DHCP snooping" is not configured but this was the original configuration during the issue.
Thank you for the configuration provided.
Few more questions:
Thank you for your answers.
Your issue seems to indicate that the "ip dhcp snooping trust" CLI command is not working properly.
By design, this command allow a port to receive DHCP OFFER from a DHCP server and, even if your configure this on the Gi1/0/19 it seems that your DHCP Requests get dropped on this interface.
To go further on this investigation, is it possible for you to activate DHCP snooping debugging "debug ip dhcp snooping event"?
This will probably helps us to understand the reason why these packets gets dropped.