On 18 Nov 2008 at 17:13, Tom Metro wrote:
> My suspicion is that the D3s are finding the tftp server using a > broadcast UDP packet to the TFTP port, and that's why it is failing to > hop the subnet. >From reading the relevant rfc's, it looks like a unicast packet http://tools.ietf.org/html/rfc1350 2. Overview of the Protocol Any transfer begins with a request to read or write a file, which also serves to request a connection. If the server grants the request, the connection is opened and the file is sent in fixed length blocks of 512 bytes. Each data packet contains one block of data, and must be acknowledged by an acknowledgment packet before the next packet can be sent. A data packet of less than 512 bytes signals termination of a transfer. If a packet gets lost in the network, the intended recipient will timeout and may retransmit his last packet (which may be data or an acknowledgment), thus causing the sender of the lost packet to retransmit that lost packet. The sender has to keep just one packet on hand for retransmission, since the lock step acknowledgment guarantees that all older packets have been received. Notice that both machines involved in a transfer are considered senders and receivers. One sends data and receives acknowledgments, the other sends acknowledgments and receives data. > You should be able to confirm this with an appropriately configured > packet sniffer. Well, there is no traffic that I see from the packet sniffer built into the router # diag sniffer packet dmz 'udp port 69' interfaces=[dmz] filters=[udp port 69] If I add port 67 or 68, I see dhcp traffic, but that's it. As per # diag sniffer packet dmz 'udp port 69 or port 67 or port 68' interfaces=[dmz] filters=[udp port 69 or port 67 or port 68] 505.911917 0.0.0.0.68 -> 255.255.255.255.67: udp 548 506.077412 10.88.65.254.67 -> 10.88.65.145.68: udp 396 No tftp traffic though :-( and no connection to the tftp server which is at 10.11.12.14, which shows up as nothing in the tftp server logs. All the devices I have here are switches, as I got rid of the last hub I had a few months back which complicates sniffing :-( I knew I should have kept that last hub around. -- Harondel J. Sibble Sibble Computer Consulting Creating Solutions for the small and medium business computer user. [EMAIL PROTECTED] (use pgp keyid 0x3AD5C11D) http://www.pdscc.com (604) 739-3709 (voice/fax) (604) 686-2253 (pager) ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Mvpmc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mvpmc-users mvpmc wiki: http://mvpmc.wikispaces.com/
