After adding a new Cisco switch to our network we can no longer communicate to our MR51e's?

A feature, when enabled, called DHCP snooping will block any DHCP reply from the controller.  Cisco Catalyst switches running iOS have this feature and I would suspect that other switch manufacturers have this or a similar feature.  Following is a brief overview of the DHCP snooping feature:

 

DHCP snooping is a security feature that acts like a firewall between untrusted hosts and trusted DHCP servers. The DHCP snooping feature performs the following activities:

• Validates DHCP messages received from untrusted sources and filters out invalid messages.

• Rate-limits DHCP traffic from trusted and untrusted sources.

• Builds and maintains the DHCP snooping binding database, which contains information about untrusted hosts with leased IP addresses.

• Utilizes the DHCP snooping binding database to validate subsequent requests from untrusted hosts.


06/21/2017