Multiple Interfaces, Not Seeing Requests

[Matthew West]

Hello FreeRADIUS List,

Thank you for taking the time to help me troubleshoot an issue: the
radiusd service on a server with two network interfaces is not
receiving RADIUS requests from network.

When requests are made locally using radtest and eapol_test (with the
EAP-MSCHAPv2 file,) the service responds just fine.  I've done both
packet-capture on the local router and a tcp dump showing packets
arriving on the server.  My guess is that the service isn't listening
to the correct interface, but it is configured to listen to all
interfaces (from what I can tell).

Environment:
    * radiusd: FreeRADIUS Version 3.0.4, for host x86_64-redhat-linux-gnu
    * CentOS Linux release 7.3.1611 (Core)
    * Network adapters:
        - ens32: 172.16.xxx.253 - used for management of server
        - ens33: 10.xxx.xxx.253 - used for RADIUS requests

radiusd -X Startup:
    # radiusd -X

    radiusd: FreeRADIUS Version 3.0.4, for host
x86_64-redhat-linux-gnu, built on Jan 17 2017 at 18:49:55
    ...
    Listening on auth address * port 1812 as server default
    Listening on acct address * port 1813 as server default
    Listening on auth address :: port 1812 as server default
    Listening on acct address :: port 1813 as server default
    Listening on auth address 127.0.0.1 port 18120 as server inner-tunnel
    Opening new proxy socket 'proxy address * port 0'
    Listening on proxy address * port 35952
    Ready to process requests

Proof packet is arriving:
23:20:50.935823 IP 10.xxx.xxx.205.1645 > 10.xxx.xxx.253.1812: RADIUS,
Access Request (1), id: 0x55 length: 49

In clients.conf:
    client NSO-ACCESS-SWI {
            ipaddr  = 10.xxx.xxx.205
            secret  = testing123
    }

I'm happy to do the legwork for this one.  Can someone point me in the
right direction for further troubleshooting?

Much Thanks,

Matthew West