[Chilli] Using external DHCP server with Coova

[Phyo Wai Soe]

Hi All,

We are using an external DHCP server with a Coova server and the issue we are facing is that sometimes Coova gives out IP addresses to clients without relaying the requests to the external DHCP server and also doesn't inform the clients of the addresses it assigned. When we release/renew the client's IP, Coova sends the request to DHCP server and client gets an address. However, it seems Coova doesn't update its MAC-DHCP address mapping and when the client with DHCP server assigned address comes, it says "Received packet with spoofed source" I have read that some people also had/have that issue but I couldn't find any solution.

It is an intermittent issue and not easily reproducible. But we think that in all those problem cases, the client already has an address, either assigned previously or a private one when it doesn't get a DHCP reply.

Here's our DHCP relay settings. We tested with the settings in local.conf and the defaults config file and they produce the same outcome. Port is not specified because we are using the default port of 67.

HS_DHCPGATEWAY=10.10.0.15
HS_DHCPRELAYAGENT=10.99.0.1

Thanks all.

Regards,
Phyo

Debug logs...
==========OK request/reply===============
dhcp.c: 5061: 0 (Debug) Layer2 PROT: 0x86dd dropped
dhcp.c: 3619: 0 (Debug) dhcp/bootps request being processed
dhcp.c: 3264: 0 (Debug) function dhcp_getreq()
dhcp.c: 732: 0 (Debug) DHCP newconn: 08:00:27:e3:0f:ff
chilli.c: 5127: 0 (Debug) New DHCP request from MAC=08-00-27-E3-0F-FF
chilli.c: 5130: 0 (Debug) New DHCP connection established
chilli.c: 5086: 0 (Debug) New Chilli Connection
dhcp.c: 3235: 0 (Debug) Sending DHCP relay packet to 10.10.0.15
dhcp.c: 3594: 0 (Debug) Not for our MAC or broadcast: 08-00-27-E3-0F-FF
dhcp.c: 5061: 0 (Debug) Layer2 PROT: 0x86dd dropped
dhcp.c: 5162: 0 (Debug) DHCP relay response from 10.10.0.15 of length 300 received
chilli.c: 4879: 0 (Debug) ----> cb_dhcp_request <----
chilli.c: 4883: 0 (Debug) DHCP request for IP address 10.99.0.10
chilli.c: 837: 0 (Debug) newip 10.99.0.10
ippool.c: 456: 0 (Debug) Requesting new static ip: 10.99.0.10
ippool.c: 479: 0 (Debug) HERE!!! -> 0
ippool.c: 482: 0 (Debug) Static IP address not allowed
ippool.c: 456: 0 (Debug) Requesting new dynamic ip: 10.99.0.10
chilli.c: 5015: 0 (Debug) Client MAC=08-00-27-E3-0F-FF assigned IP 10.99.0.10

====Non-OK request/reply=====
dhcp.c: 732: 0 (Debug) DHCP newconn: 08:00:27:e3:0f:ff
chilli.c: 5128: 0 (Debug) New DHCP request from MAC=08-00-27-E3-0F-FF
chilli.c: 5131: 0 (Debug) New DHCP connection established
chilli.c: 5087: 0 (Debug) New Chilli Connection
dhcp.c: 5686: 0 (Debug) ARP: 08-00-27-E3-0F-FF asking about 91.189.89.134
chilli.c: 4880: 0 (Debug) ----> cb_dhcp_request <----
chilli.c: 4884: 0 (Debug) DHCP request for IP address 169.254.9.47
chilli.c: 837: 0 (Debug) newip 169.254.9.47
ippool.c: 456: 0 (Debug) Requesting new static ip: 169.254.9.47
ippool.c: 479: 0 (Debug) HERE!!! -> 0
ippool.c: 482: 0 (Debug) Static IP address not allowed
ippool.c: 456: 0 (Debug) Requesting new dynamic ip: 169.254.9.47
chilli.c: 5016: 0 (Debug) Client MAC=08-00-27-E3-0F-FF assigned IP 10.99.0.2
=============================