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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am currently making use of dnsmasq in an embedded Linux environment which supports Wi-Fi clients. One of the requirements for this device is that it is able to support 120 simultaneous Wi-Fi connections. In the past I was using dnsmasq
version 2.76. I would run a test where all 120 clients would request connections in a very short time span and dnsmasq was able to assign an IP address to each client in about 1 minute. For security reasons I later had to update to version 2.78 of dnsmasq.
I now find that it takes far longer to connect these 120 Wi-Fi clients. What used to take 1 minute now takes 6 or more minutes. I’ve done a bit of digging in the code and the behavior observed seems to be related to the do_icmp_ping function and the integer
max defined in this function. It gets set to six and so I observe that 6 clients can be assigned IP addresses right away. After that all other clients will have their DHCPDISCOVERs ignored with a log message of “No addresses available” printed until 30s has
passed and then the next group of 6 will receive their addresses.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is anyone familiar with this behavior? Is there a known workaround? I have attached the dnsmasq.conf file that I’m using. The Wi-Fi interface is uap0 and has been given the range 100 – 250 so I would expect when I connect 120 clients to
never receive a message indicating that there are no remaining addresses.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Daniel Miess<o:p></o:p></p>
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