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<div>RFC 5375 advises against prefixes longer than /64. </div>
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<div dir="ltr"><a href="https://datatracker.ietf.org/doc/html/rfc5375#appendix-B.2">https://datatracker.ietf.org/doc/html/rfc5375#appendix-B.2</a><br>
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<div dir="ltr">A /48 gives you 65535 /64’s, why not use some of them?</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size: 11pt;" data-ogsc=""><b>From:</b> ipv6-ops-bounces+kristian.mccolm=rci.rogers.com@lists.cluenet.de <ipv6-ops-bounces+kristian.mccolm=rci.rogers.com@lists.cluenet.de>
on behalf of Doug Hardie <bc979@lafn.org><br>
<b>Sent:</b> Sunday, June 27, 2021 2:54:01 PM<br>
<b>To:</b> ipv6-ops@lists.cluenet.de <ipv6-ops@lists.cluenet.de><br>
<b>Subject:</b> Prefix delegation to sub nets</font>
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<div class="PlainText">I am trying to setup an IPv6 environment. There is a primary router (A) that receives a /48 prefix via DHCP6 from the ISP. That router configures itself properly via dhcp6c. It also creates 2 LAN /64 prefixes and creates EUI-64 addresses
on the two LAN interfaces. One of those interfaces is connected to a second router (B), among other devices. The B router receives the prefix via SLAAC and creates its own EUI-64 address. However, that router needs to create a smaller subnet, /72, and distribute
it to the devices on that LAN. I have not been able to figure out how to make that happen.<br>
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Clearly, manual configuration would work, but the prefix received from the ISP can change which would raise havoc with the network. I suspect that dhcp6s needto be run alongside dhcp6c on router B and then the other devices run dhcp6c. However, I don't see
how to get the prefix that dhcp6c receives on router B to the dhcp6s process on router B. I believe I am missing something, but haven't been able to find it. Thanks,<br>
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-- Doug<br>
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