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<p class=MsoNormal>Hello,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-US>i would like to know how to resolve a problem.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I have a debian router with 3 interfaces
(LAN, and two internet providers (Provider A, Provider B)).<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>The default route is configured to use the
provider A<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>The problem is that,<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>When an external connection arrives from
provider B to an internal server (with nat), the packet is routed to the
default route:<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I explain:<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo4'><![if !supportLists]><span
lang=EN-US><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span lang=EN-US>A packet arrives from provider
B in direction of a internal server<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo4'><![if !supportLists]><span
lang=EN-US><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span lang=EN-US>The router performs nat
operation<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo4'><![if !supportLists]><span
lang=EN-US><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span lang=EN-US>The internal server generates a
response<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-18.0pt;mso-list:l1 level1 lfo4'><![if !supportLists]><span
lang=EN-US><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span lang=EN-US>The router routes the packet on
the interface Provider A<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Consequently, The connection cannot been
established <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I want to know if its possible to configure
my debian router to route packets to the interface on which packet arrives. In
the example, packets should have been routed by the interface connected to
provider B<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>If yes, do you know how to do that ?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Thanks.</span><o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
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