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<p class="MsoNormal"><span lang="NL">Hi All,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="NL"><o:p> </o:p></span></p>
<p class="MsoNormal">I have performed several test and already have opened one thread about this issue. I have seen unexpected behavior on android when DHCPv4 client tries to reuse a previously allocated network address and this address is unavailable on the
server.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The test steps are the following:<o:p></o:p></p>
<ol style="margin-top:0cm" start="1" type="1">
<li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">Set the range of DHCP leases to only 1. Until now, DHCP can only lease one address.<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">Connect a device and get the only IPv4 address lease available then disconnect.<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">On the server dnsmasq leases file, replace the IPv4 lease and give the address to other machine.<o:p></o:p></li><li class="MsoListParagraph" style="margin-left:0cm;mso-list:l0 level1 lfo1">Reconnect the device on point 1.<o:p></o:p></li></ol>
<p class="MsoListParagraph"><o:p> </o:p></p>
<p class="MsoNormal">Basically on windows and IOS I can see that the first message on the DHCP client-server communication is a DHCPREQUEST sent by the client with the IPV4 address that wants to reuse. Then, the server respond with a DHCPNAK indicating the
lease is not available anymore on the server. After that the client tries to get a new IPV4 but is not possible because no IPV4 range is available. (the only available address is assigned).
<o:p></o:p></p>
<p class="MsoNormal">This is the correct behavior indicated on RFC1531<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">However, on Android the DHCPv4 client does not use DHCPREQUEST and then it reuses the address even when that address has been reassigned to other machine.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Did someone experience that?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards and thanks in advance<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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