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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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I have a question about kea-dhcp4 configuration related to server local address.<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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Kea administration guide explains that you can specify a list of interfaces on which the server will listen, such as:<o:p></o:p></span></p>
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<span style="font-size:10.5pt;font-family:"Courier New";color:#333333">"interfaces": [ "eth0", "eth1" ],<o:p></o:p></span></p>
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<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Is it possible to restrict this to a single IP address for a given interface ?<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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">With ISC’s dhcpd, this was achieved with the configuration item “local-address”.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This allowed to start multiple servers on the same host, using the same interface, but each having its own local IP address.<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 did not find a similar option with kea ; did I miss something ?<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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I tested the following scenario:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- Start a dhcpd, which listens on a given interface, and binds to a specific local IP addr<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">- Start kea-dhcp4, with the same interface as used by dhcpd<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Kea starts, but compains that it cannot bind to the IP addr used by dhcpd:<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-left:35.4pt"><span lang="EN-US">2014-09-04 11:15:23.386 WARN [kea-dhcp4.dhcp4/7595] DHCP4_OPEN_SOCKET_FAIL failed to open socket: failed to open socket on interface eth0.102, reason: failed to bind fallback socket to address
10.163.216.229, port 67, reason: Address already in use - is another DHCP server running?<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">Then, if a DHCP message is sent by a relay to dhcpd local IP addr, two responses are sent back: both dhcpd and kea manage to answer! (even though kea couldn’t bind to this IP address, apparently the interface is enough)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">This is weird. <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"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">On the opposite, if I start first kea, then dhcpd, dhcpd fails to start because it cannot bind on the local address:<o:p></o:p></span></p>
<p class="MsoNormal" style="text-indent:35.4pt"><span lang="EN-US">Can't bind to dhcp address: Address already in use<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"><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">Is this the intended behavior ?<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"><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 for your time.<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">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Nicolas.<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"><o:p> </o:p></span></p>
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