DHCP falls back but no response to ping

Rabbit Rabbit Software
,
1

I am seeing issues with DHCP on RCM6700 using 10.72.

Sometimes the module falls back to fallback address however I cannot ping the device. The network is the same, I simply reboot and try again and both DHCP or fallback can work.

I have reverted back to running the DHCP.c example and can still see the problem. I am doing a soft reset to reproduce, sometimes it takes a number of restart program attempts to see the fail.

I am pinging both the fallback and the dhcp address on a different machine.

Anyone any suggestions on what is going on here or what I may be doing wrong?

Thanks if you have read this far.

This is the output with some debug when it fails:
========= DHCP.C =========
Enter the following keystrokes:
0-9 toggle specified interface up/down
p ping a host
P ping the same host again
w do a HTTP HEAD request to specified host
W HTTP HEAD from the same host again
t print the interface, router, ARP and DNS server tables
r add a router entry
R delete a router entry
n add a nameserver (DNS) entry
N delete a nameserver entry
f flush an ARP table entry
i set new IP address and netmask

IP: pkt_init reserved 10 buffers at 000FB09A
IP: i/f 0 using hwa :00:90:C2:FD:B4:FC
Interface 0 is qualified for DHCP.
Starting network (DHCP timeout 8 seconds)…
Done sock_init()
TCP: -8217ms since last call to tcp_tick!
DHCP: Sending DISCOVER request on i/f 0
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: overall timeout (6 sec)
DHCP: Didn’t acquire lease on i/f 0
DHCP: Fallback to c0a896cd on i/f 0

Interface # 0 is now UP

Network Parameters:
My IP Address = C0A896CD
Netmask = FFFFFF00
DHCP fell back to defaults

Interface table:

IP addr. Mask Up Lnk Type MTU Flags Peer/router

0 192.168.150.205 255.255.255.0 yes yes eth 1500 *D S

Nameserver list:

= = = = = = = = = = = = = = =

TCP: 291ms since last call to tcp_tick!
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: Sending DISCOVER request on i/f 0
TCP: 200ms since last call to tcp_tick!
TCP: 101ms since last call to tcp_tick!
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: overall timeout (6 sec)
DHCP: Didn’t acquire lease on i/f 0
DHCP: Fallback to c0a896cd on i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: driving state machine for i/f 0
DHCP: Sending DISCOVER request on i/f 0
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: retransmit in state 16 -> 13
DHCP: Sending DISCOVER request on i/f 0
DHCP: overall timeout (6 sec)
DHCP: Didn’t acquire lease on i/f 0
DHCP: Fallback to c0a896cd on i/f 0
DHCP: driving state machine for i/f 0

2

For your test, I assume you’re pinging from a machine with an IP address on the 192.168.150.x network, also with a netmask of 255.255.255.0.

Please upgrade to Dynamic C 10.72D and see if that resolves the issue. Go to the “Development Software” section of this page to download the installer: https://www.digi.com/support/productdetail?pid=4978

Or if you’re comfortable with using Git, you can work with this repository: https://github.com/digidotcom/DCRabbit_10

I made a change that went into 10.72C related to DHCP fallback/recovery that may apply to your situation.

https://github.com/digidotcom/DCRabbit_10/commit/62466f2893d921accc64602cabe3efae8302c1da