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I have ubuntu router questions. you can see tracert can complete on way but not other way. How to make that work?

(a better visual layout exists here)

This way from second win7 works to first win7


Tracing route to WIN7 []
over a maximum of 30 hops:

  1    <1 ms    <1 ms    <1 ms  SCOTT-P5QC []
  2    <1 ms    <1 ms    <1 ms []
  3    25 ms    24 ms    31 ms  WIN7 []
  4    18 ms    17 ms    40 ms  WIN7 []

Trace complete.


This way from first win7 to second win7 broken


Tracing route to over a maximum of 30 hops

  1    52 ms     1 ms     1 ms []
  2    43 ms    98 ms    45 ms
  3    45 ms   105 ms    24 ms  SCOTT-PC []
  4  SCOTT-PC []  reports: Destination protocol unreachable.</pre>

Trace complete.

From first win7 to ubuntu router works


Tracing route to SCOTT-P5QC []
over a maximum of 30 hops:

  1   105 ms    <1 ms     4 ms []
  2    19 ms    17 ms    33 ms
  3    35 ms    34 ms     5 ms  SCOTT-P5QC []</pre>

Trace complete.


netstat routes in ubuntu router

scott@scott-P5QC:~$ netstat -r
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
default         UG        0 0          0 eth2       *        U         0 0          0 eth0
link-local      *          U         0 0          0 eth0     *        U         0 0          0 eth2
scott@scott-P5QC:~$ </pre>

hand copy of lan layout


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solved by installing webmin. Then used it to reset iptables. Seriously great tool for administering the firewall. Webmin told me 2 rules were in the iptables which it could not understand, so I save iprules to a file, did a reset and all 3 pc can share files.

a firewall is defacto running all the time with iptables, so those tables must be modified.

scott@scott-P5QC:~$ sudo dpkg -i webmin_1.580_all.deb Selecting previously unselected package webmin. (Reading database ... 229686 files and directories currently installed.) Unpacking webmin (from webmin_1.580_all.deb) ... Setting up webmin (1.580) ... Webmin install complete. You can now login to xxxxxxxxxxxxxxxxxxx as root with your root password, or as any user who can use sudo to run commands as root. Processing triggers for ureadahead ... ureadahead will be reprofiled on next reboot scott@scott-P5QC:~$

shows what it looks like

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