10 Replies Latest reply on Jul 12, 2007 1:37 PM by jtsu1

    TFTP with mutiple NIC's

      Hi All,


      I have moved TFTP from a single NIC server to a dual NIC server.  On the Single NIC server all worked perfectly.  On the Dual NIC server it only works if I disable the NIC I don't won't TFTP to listen on.

      With the 2nd NIC enabled it appers the file starts to download then times out.

       


       


       


       Any ideas anyone. 


       Thanks


      Caniwi


      Version - 8.27

        • Re: TFTP with mutiple NIC's
          jtimes

          What is the setup of the NICs in the OS?  Load balanced, Switch Assisted Load balancing, or Fault Tolerant? TFTP uses UDP, so it's traffic is only going to go to one MAC and will intermittently fail if your NICs are load balancing (unless it's switch assisted load balancing.) 

            • Re: TFTP with mutiple NIC's

              The two nics are on two seperate networks 192.168.0.12/24 & 192.168.100.20/24 are the two IPs for the server.  The OS is Windows 2003 Server.


              I want the TFTP server to respond to requests on x.x.100.20, which only happens if I disable the x.x.0.12 NIC.


              On opening the TFTP console, it displays x.x.0.12.  If I close the console and disable the NIC and then restart the console it displays x.x.100.20.  All works as expected.  If I then renable x.x.0.12, the TFTP stops responding/sending information and the client times out.


              I hope this extra information might help in diagnosing this issue.


              Caniwi


               


               


                • Re: TFTP with mutiple NIC's
                  jtimes

                  Are both NICs registered in DNS with the same server name?


                  Can you hard code the TFTP server ip on the remote device you are sending/receiving?

                    • Re: TFTP with mutiple NIC's

                      Thanks for the quick response.


                      I am thinking no to your first question.  In DNS the two records look like;


                      (same as parent folder)  Host (A)  192.168.0.12


                      admain                         Host (A)  192.168.100.20


                       


                      I am using the TFTP server to push out the Thinstation client to some PXE enabled PC's.  Of course they use DHCP to find out the TFTP server's IP.


                      Thanks


                      Caniwi

                        • Re: TFTP with mutiple NIC's
                          jtimes

                          Only one last option at this point...  Sniff it to see whats happening from the client station side.

                            • Re: TFTP with mutiple NIC's

                              Hi John,


                               Nothing better to do than look at these forums :-)


                               Again thanks for the quick response.  I will see if I have time tomorrow to do the sniffing.  I will keep you posted


                               


                              Caniwi

                                • Re: TFTP with mutiple NIC's
                                  Network_Guru


                                  Hi John,

                                   Nothing better to do than look at these forums :-)

                                   Again thanks for the quick response.  I will see if I have time tomorrow to do the sniffing.  I will keep you posted

                                  Caniwi

                                   

                                   

                                  Hey Caniwi, try running this command from the command prompt:

                                   C:\WINDOWS>route print

                                  You should see something like this:

                                   ===========================================================================
                                  Interface List
                                  0x1 ........................... MS TCP Loopback interface
                                  0x3 ...00 12 3f mc x7 zf ...... Broadcom NetXtreme 57xx Gigabit Controller - SecuRemote Miniport
                                  0x20002 ...00 14 a5 21 bb gg ...... Dell Wireless 1470 Dual Band WLAN Mini-PCI Card
                                  ===========================================================================
                                   Active Routes:
                                  Network Destination        Netmask          Gateway       Interface  Metric
                                            0.0.0.0          0.0.0.0    192.168.2.254   192.168.2.100       25
                                          127.0.0.0        255.0.0.0        127.0.0.1       127.0.0.1       1
                                        192.168.2.0    255.255.255.0    192.168.2.100   192.168.2.100       25
                                      192.168.2.100  255.255.255.255        127.0.0.1       127.0.0.1       25
                                      192.168.2.255  255.255.255.255    192.168.2.100   192.168.2.100       25
                                          224.0.0.0        240.0.0.0    192.168.2.100   192.168.2.100       25
                                    255.255.255.255  255.255.255.255    192.168.2.100               3       1
                                    255.255.255.255  255.255.255.255    192.168.2.100   192.168.2.100       1
                                    255.255.255.255  255.255.255.255    192.168.2.100               4       1
                                  Default Gateway:     192.168.2.254
                                  ===========================================================================
                                  Persistent Routes:
                                    None

                                  <HR> 

                                  It's most likely sending the UDP traffic on the Interface listed first & with the lowest metric.
                                  You can also try adding a persistent route with a lower metric for the TFTP subnet you are trying to access.

                                  <HR> 

                                  C:\WINDOWS>route add ?

                                  Manipulates network routing tables.

                                  ROUTE [-f] [-p] [command [destination]
                                                    [MASK netmask]  [gateway] [METRIC metric]  [IF interface]

                                    -f           Clears the routing tables of all gateway entries.  If this is
                                                 used in conjunction with one of the commands, the tables are
                                                 cleared prior to running the command.
                                    -p           When used with the ADD command, makes a route persistent across
                                                 boots of the system. By default, routes are not preserved
                                                 when the system is restarted. Ignored for all other commands,
                                                 which always affect the appropriate persistent routes. This
                                                 option is not supported in Windows 95.
                                    command      One of these:
                                                   PRINT     Prints  a route
                                                   ADD       Adds    a route
                                                   DELETE    Deletes a route
                                                   CHANGE    Modifies an existing route
                                    destination  Specifies the host.
                                    MASK         Specifies that the next parameter is the 'netmask' value.
                                    netmask      Specifies a subnet mask value for this route entry.
                                                 If not specified, it defaults to 255.255.255.255.
                                    gateway      Specifies gateway.
                                    interface    the interface number for the specified route.
                                    METRIC       specifies the metric, ie. cost for the destination.

                                  All symbolic names used for destination are looked up in the network database
                                  file NETWORKS. The symbolic names for gateway are looked up in the host name
                                  database file HOSTS.

                                  If the command is PRINT or DELETE. Destination or gateway can be a wildcard,
                                  (wildcard is specified as a star '*'), or the gateway argument may be omitted.

                                  If Dest contains a * or ?, it is treated as a shell pattern, and only
                                  matching destination routes are printed. The '*' matches any string,
                                  and '?' matches any one char. Examples: 157.*.1, 157.*, 127.*, *224*.
                                  Diagnostic Notes:
                                      Invalid MASK generates an error, that is when (DEST & MASK) != DEST.
                                      Example> route ADD 157.0.0.0 MASK 155.0.0.0 157.55.80.1 IF 1
                                               The route addition failed: The specified mask parameter is invalid. (Destination &
                                  Mask) != Destination.

                                  Examples:

                                      > route PRINT
                                      > route ADD 157.0.0.0 MASK 255.0.0.0  157.55.80.1 METRIC 3 IF 2
                                               destination^      ^mask      ^gateway     metric^    ^
                                                                                           Interface^
                                        If IF is not given, it tries to find the best interface for a given
                                        gateway.
                                      > route PRINT
                                      > route PRINT 157*          .... Only prints those matching 157*
                                      > route CHANGE 157.0.0.0 MASK 255.0.0.0 157.55.80.5 METRIC 2 IF 2

                                        CHANGE is used to modify gateway and/or metric only.
                                      > route PRINT
                                      > route DELETE 157.0.0.0
                                      > route PRINT
                                   
                                   

                                    • Re: TFTP with mutiple NIC's

                                      Try to change the order of the NICs so the 100.20 NIC is first one traffic will use

                                       

                                      Tim


                                      • Re: TFTP with mutiple NIC's

                                        i have a dual nic server, one on the site LAN and the other on the private LAN. when i copy-tftp my cisco switch's config file on the site LAN to my server, it works.


                                         however, when i copy-tftp an identical cisco switch's config file on the private LAN to my server, it fails with "%Error opening tftp://192.168.202.5/save-config (Timed out)".  I tried disabling the site LAN network connection and restarting the TFTP server to no avail.


                                        Any ideas?


                                        Thx. 

                          • Re: TFTP with mutiple NIC's

                            Hi Caniwi,


                            I was trying to run Solarwinds FTP on my laptop with multiple NICS but for some reason it kept on saying that there is another tftp server running on port 69 even though there was not. So I opted for an alternative which was TFTPutil, it's open source and available on sourceforge. TFTPutil ran but would time out transfers until I specified which IP (NIC) to listen on. If your TFTP server supports multiple addresses try to specify the address of the NIC you want to run it on. This should work... Do let us know your findings.


                             Regards,


                            Spiros.