<div dir="auto"><div>Does anybody here knows what Gambiarra means?<div dir="auto"><br></div><div dir="auto">Alejandro mentioned that IPv6 NextHop on IPv4 routing breaks traceroute and difficult troubleshooting.</div><div dir="auto"><br></div><div dir="auto">Well... Since a while I have been thinking about a Gambiarra that I'm using on other scenarios, but I think could help to reduce de bad impacts of IPv6 NextHop on IPv4 routing.</div><div dir="auto"><br></div><div dir="auto">O router with several interfaces with IPv6 only and at least one public IPv4 /32 on his loopback.</div><div dir="auto">On the IPv4 address on each of that v6 only interfaces, use "IP address unnumbered loopback 0".</div><div dir="auto"><br></div><div dir="auto">This would make the ICMP responses for TTL expired be sourced with that public IPv4.</div><div dir="auto"><br></div><div dir="auto">Would not be as good as one public IP for each interface, but at least, on a traceroute, would be possible to Defined what ASN is responsible for that hop, and exactly in what router it occurs.</div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">Em qua, 29 de jul de 2020 08:25, Alejandro Acosta <<a href="mailto:alejandroacostaalamo@gmail.com">alejandroacostaalamo@gmail.com</a>> escreveu:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p>Long time ago I tried it out:</p>
<p><a href="https://blog.acostasite.com/2013/02/publicar-prefijos-ipv4-sobre-una-sesion.html" target="_blank" rel="noreferrer">https://blog.acostasite.com/2013/02/publicar-prefijos-ipv4-sobre-una-sesion.html</a></p>
<p><a href="https://blog.acostasite.com/2013/02/publicando-prefijos-ipv6-sobre-sesiones.html" target="_blank" rel="noreferrer">https://blog.acostasite.com/2013/02/publicando-prefijos-ipv6-sobre-sesiones.html</a></p>
<p><br>
</p>
<p>I did not like, difficult troubleshooting in case something goes
wrong (however I can understand it's a nice feature to have and in
might be useful in some scenarios).<br>
</p>
<p><br>
</p>
<p>But you are right I do not know much about networks doing it, I
also would like hear about it.</p>
<p><br>
</p>
<p>Alejandro,<br>
</p>
<p><br>
</p>
<div>On 7/29/20 1:51 AM, Douglas Fischer
wrote:<br>
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<div class="gmail_default"><font face="monospace">Let's just jump all the arguing about lack
of IPv4, the need of IPv6, and etc...<br>
<br>
I must confess that I don't know all the RFCs.<br>
I would like it, but I don't!</font></div>
<div class="gmail_default"><font face="monospace"><br>
</font></div>
<div class="gmail_default"><font face="monospace">And
today, I reached on <a href="https://tools.ietf.org/html/rfc5549" target="_blank" rel="noreferrer">https://tools.ietf.org/html/rfc5549</a></font></div>
<div class="gmail_default"><font face="monospace"><br>
I knew that was possible to transfer v4 routes over v6 BGP
sessions, or v6 routes over v4 BGP sessions.<br>
But I got surprised when I saw this youtube vídeo of AMS-IX
guys considering use a v6 only Lan, and doing v6 next-hops
to v4 routes.<br>
</font></div>
<div class="gmail_default"><font face="monospace"><a href="https://www.youtube.com/watch?v=uJOtfiHDCMw" target="_blank" rel="noreferrer">https://www.youtube.com/watch?v=uJOtfiHDCMw</a> <br>
</font></div>
<div class="gmail_default"><font face="monospace"><br>
Well... I guess that idea didn't go to production.<br>
</font></div>
<div class="gmail_default"><font face="monospace"><br>
<br>
<br>
But the questions are:<br>
There is any network that really implements RFC5549?<br>
Can anyone share some information about it?</font></div>
<div class="gmail_default"><font face="monospace"><br>
</font></div>
<font face="monospace">-- <br>
</font>
<div dir="ltr" data-smartmail="gmail_signature"><font face="monospace">Douglas
Fernando Fischer<br>
Engº de Controle e Automação</font></div>
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