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<p class="MsoNormal">I have two systems where I need them to assign link-local addresses in a 169.254.4/24 subnet, regardless of any other addresses configured. I’m using a /24 subnet because I have multiple interfaces on the system that require link-local
addresses; I was placing them in their own subnets. <o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">From <a href="https://www.freedesktop.org/software/systemd/man/latest/systemd.network.html#:~:text=If%20an%20IPv4%20link%2Dlocal%20address%20(169.254.0.0/16)%20is%20specified%2C%20IPv4%20Address%20Conflict%20Detection%20(RFC%205227)%20is%20enabled%20for%20the%20address.">
this comment</a> in the man page, I was expecting I could configure the interface address identically on both systems and leave it to collision detection to pick an appropriate available address.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The 1<sup>st</sup> interface assigns its link-local address (169.254.4.2/24). Unfortunately, the next interface to start doesn’t assign any link-local address. I’ve tried to get more debug information by increasing log-level to debug, but
I get no indications around the address assignments.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">As an experiment, I change the 2<sup>nd</sup> system to use a different host address in the same subnet, and it gets assigned correctly. I guess that collision detection is preventing the address assignment.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">How do I achieve this or how can I get more debug information?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The relevant snippet from the network config file is:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Network]<o:p></o:p></p>
<p class="MsoNormal">Address=169.254.4.2/24<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Full contents of the network configuration follows:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">$ networkctl cat 10-eno0.network<o:p></o:p></p>
<p class="MsoNormal"># /etc/systemd/network/10-eno0.network<o:p></o:p></p>
<p class="MsoNormal">[Match]<o:p></o:p></p>
<p class="MsoNormal">KernelCommandLine=!nfsroot<o:p></o:p></p>
<p class="MsoNormal">Name=eno0<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[DHCP]<o:p></o:p></p>
<p class="MsoNormal">ClientIdentifier=mac<o:p></o:p></p>
<p class="MsoNormal">RouteMetric=10<o:p></o:p></p>
<p class="MsoNormal">UseDomains=yes<o:p></o:p></p>
<p class="MsoNormal">UseHostname=yes<o:p></o:p></p>
<p class="MsoNormal">UseMTU=yes<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[IPv6AcceptRA]<o:p></o:p></p>
<p class="MsoNormal">UseRedirect=no<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Link]<o:p></o:p></p>
<p class="MsoNormal">RequiredForOnline=no<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">[Network]<o:p></o:p></p>
<p class="MsoNormal">DHCP=yes<o:p></o:p></p>
<p class="MsoNormal">Domains=labs.company.net<o:p></o:p></p>
<p class="MsoNormal">NTP=10.10.135.123<o:p></o:p></p>
<p class="MsoNormal"># LinkLocalAddressing=yes<o:p></o:p></p>
<p class="MsoNormal"># IPv4LLStartAddress=169.254.1.1<o:p></o:p></p>
<p class="MsoNormal">Address=169.254.4.2/24<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"># /usr/lib/systemd/network/10-eno0.network.d/10-network.conf<o:p></o:p></p>
<p class="MsoNormal">[Network]<o:p></o:p></p>
<p class="MsoNormal">MulticastDNS=yes<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">Matt.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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