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<p class="MsoNormal"><span lang="DE-CH">Hi<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE-CH"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Isc-dhcpd ignores dhcprequest from clients that come from an unknown segment. In the logs it looks like this:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="p1"><span class="s1">DHCPREQUEST for 10.65.1.179 from </span><span class="s1"><span lang="EN-US">MAC:ADDR</span></span><span class="s1"> via 10.65.0.1: ignored (unknown subnet).</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="DE-CH"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">What I get from kea-dhcp4 is this:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="p1"><span class="s1">ERROR [kea-dhcp4.bad-packets/435270.139990395717376] DHCP4_PACKET_NAK_0001 [hwtype=1
</span><span class="s1"><span lang="EN-US">MAC:ADDR</span>], cid=[</span><span class="s1"><span lang="EN-US">MAC:ADDR</span>], tid=0x52eec91a: failed to select a subnet for incoming packet, src
</span><span class="s1">10.65.0.1, type DHCPREQUEST</span><o:p></o:p></p>
<p class="p1"><span class="s1">ERROR [kea-dhcp4.bad-packets/435270.139990395717376] DHCP4_PACKET_NAK_0001 [hwtype=1
</span><span class="s1"><span lang="EN-US">MAC:ADDR</span>], cid=[</span><span class="s1"><span lang="EN-US">MAC:ADDR</span>], tid=0x52eec91b: failed to select a subnet for incoming packet, src
</span><span class="s1">10.65.0.1, type DHCPDISCOVER</span><span class="s1"><span lang="EN-US"><o:p></o:p></span></span></p>
<p class="p1"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Kea sends dhcpnak to clients from subnets it is not configured to serve. If the same client keeps coming back, it will not get an IP address. This is what is happening.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">It would be very helpful if kea would ignore these requests, much like isc-dhcp does. Is it possible to configure this?<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 am aware of dhcp helpers. There would be no such logs if we had dhcp helpers in our network. Currently, we don’t. Our network guys work (and the hardware vendor) work on it.
<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,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Philipp<o:p></o:p></span></p>
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