Cannot establish FTP connection with Connect ME 9210 Dev Kit after setting IP with Serial Port

Question

Hi I am writing a script to automate the loading of rom.bin over an FTP connection between Digi Connect ME 9210s on Dev boards from a PC running Windows 7. My exact Digi right now is DC-ME-01T-C. My Perl code loads a custom (the author is no longer in my group) Net OS image without issue, then deselects DHCP, assigns an IP address, subnet mask and Gateway to the Digi on the dev board through a serial connection. After, I am able to ping the device from a command prompt but am unable to open an FTP session to load the corresponding rom.bin (loading the same image from netosprog.exe and setting the IP, etc from a terminal emulator yields the same results). Before the image is loaded, I can open an FTP session, using the default UN and PW but when the OEM image is overwritten I can no longer establish an FTP connection. Is there a simple parameter I am over looking setting in the handshake process that enables FTP sessions, or a flag I need to set or some sort of authorization I have to grant? Trying to avoid having to snake leads into the digi's in our lab that are wired to controllers to see how the handshake occurs there. Thank you for any help

Answer 1

>when the OEM image is overwritten I can no longer establish an FTP connection.
It sounds like you are programming image.bin with application that does not include ftp server. That would explain why you can ping but can't ftp

Comments

When I take the same  physical digi programmed with the same application from my dev board (that is able to be pinged but not able to establish an FTP or Telnet) and put it in the production chassis where the link is established with C on an Atmel controller, I am able to open both an FTP and Telnet session. We have searched through the code and cannot discern what I am missing, if there is an inital read done by the Digi (before the DHCP state, IP, mask and gateway is passed), that allows those kinds of connections, or a closing symbol passed.

Answer 2

Hello

"Before the image is loaded, I can open an FTP session, using the default UN and PW but when the OEM image is overwritten I can no longer establish an FTP connection"

I would recommend using a tool such as wireshark to monitor the network traffic between the device and the PC that is attempting to establish an FTP connection. This will tell you whether the problem is that 1) there is no FTP server on the device at all, or 2) The FTP server is on the device but you have either the username, password or both wrong when trying to establish an ftp session with the device.

Comments

I did try that with HHD Serial Port monitor, and could see the exchange clearly where there is no FTP, unfortunately I think to really see what is going on I will need to peak in on the exchange between the controller and Digi in the chassis. Though the work of coding and getting wires in between there with a board is what I was trying to avoid. Thank you dakotas_dad and LeonidM for your help so far. I will try Wire Shark, see if I can tell whether or not the FTP server is present, but I am almost certain it is as the same image works in the other chassis with the other code. I should have said earlier I am not getting even the chance to enter a UN or PW after I load my new image.bin. When I try to begin my FTP session my resultant output is.
" >ftp 192.168.101.xxx
ftp>"
The welcome screen prompting for UN and PW does not appear. And when I attempt to establish a telnet session, I get an error saying connection failed. Both of which work for the same Digi with the same image in the prod chassis.

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When I inspected the connection attempt with Wireshark here is a transcript of the exchange:
"PC IP (src) Device IP (Dest) wip-port > ftp [syn] seq=0 win=8192 Len=0 MSS=1460 WS=4 SACK_PERM=1;
Device  IP (src) PC IP (DEST) ftp > wip-port [RST, ACK] seq=1 ack=1 win=0 len=0 ;
pcIP DevIP [TCP Retransmission] 1st message repeated;
1st response repeated;
same retransmission with the same response again"
TY again for your suggestions and help

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"PC IP (src) Device IP (Dest) wip-port > ftp [syn] seq=0 win=8192 Len=0 MSS=1460 WS=4 SACK_PERM=1;
Device  IP (src) PC IP (DEST) ftp > wip-port [RST, ACK] seq=1 ack=1 win=0 len=0 ;
pcIP DevIP [TCP Retransmission] 1st message repeated;

Hello
    If you are seeing a reset then either FTP is not running at all or for some reason the FTP port is shutdown.

Answer 3

do you also have backup image in FLASH? perhaps it is booting it instead of the main image. Otherwise the code might be stuck somewhere before the FTP server starts waiting in some endless loop. There should be no reason why ping works , but other TCP communications don't unless there is a firewall in between.

Comments

LeonidM, I believe it is the correct image as when I have OEM image loaded I get the prompt for UN and PW and it accepts the defaults for an FTP session, then when I re-image I no longer get the prompt. But I am unsure if I am drawing the wrong conclusion form that fact, if that may be so is there a way I can check which image is booting?

As to the endless loop regard, that is definitely a possibility, this is what I came to as an initial conclusion, that maybe I am missing a transmit value that is sent by the C code on the production controller to the Digi that is required to break that loop or authorize FTP connections or something. I really hope not though b/c that requires the wiring/board/code to peak in between the Atmel and Digi in the prod chassis that I was hoping to avoid.

Thank you again

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Sorry, forgot to mention, I did check my windows firewall, initially when I encountered this problem and again when you recommended to do so this morning. It seems I have all the permissions set properly for FTP (client, server (Passive and secure as well) and the relevant ports) If you guys are nice enough to suggest a solution, I will not dismiss anything.