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</o:shapelayout></xml><![endif]--></head><body lang=EN-IE link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Perhaps the presence of the ‘direct’ keyword combined with a manual ‘interface X’ in a protocol block could signal to bypass the usual evaluation and force a neighbor to be considered ‘direct’?<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Regards,<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'>Cathal.<o:p></o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><p class=MsoNormal><span style='mso-fareast-language:EN-US'><o:p> </o:p></span></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0cm 0cm 0cm'><p class=MsoNormal><b><span lang=EN-US>From:</span></b><span lang=EN-US> Bird-users <bird-users-bounces@network.cz> <b>On Behalf Of </b>Arzhel Younsi<br><b>Sent:</b> Tuesday 14 May 2024 14:58<br><b>To:</b> Ondrej Zajicek <santiago@crfreenet.org><br><b>Cc:</b> bird-users@network.cz<br><b>Subject:</b> Re: BGP on /32 (/128) interfaces<o:p></o:p></span></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Thank you all for your replies,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>> Thinking about it, it makes sense to have something like direct mode that works with unnumbered interfaces (or ones with /32 address).<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>We also think that's would be very useful, either transparently to the user (depending on next hop resolution, eBGP/iBGP, IP's subnet mask) or through the addition of an explicit "direct" keyword.<o:p></o:p></p></div><div><p class=MsoNormal>What would be the process to turn this thread into a feature request ? And would the Bird maintainers be interested in implementing it ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thanks again !<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Mon, Apr 15, 2024 at 4:25 PM Ondrej Zajicek <<a href="mailto:santiago@crfreenet.org">santiago@crfreenet.org</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0cm 0cm 0cm 6.0pt;margin-left:4.8pt;margin-right:0cm'><p class=MsoNormal>On Mon, Apr 15, 2024 at 12:10:05PM +0200, Daniel Gröber wrote:<br>> Hi Arzhel,<br>> <br>> On Fri, Apr 12, 2024 at 11:57:38AM +0200, Arzhel Younsi wrote:<br>> > But for IPv6, it's cleaner to only require the router's link local address:<br>> > testvm2006:~$ ip -6 addr<br>> > inet6 2620:0:860:140:10:192:24:4/128 scope global<br>> > testvm2006:~$ ip -6 route<br>> > default via fe80::2022:22ff:fe22:2201 dev ens13 metric 1024 pref medium<br>> > <br>> > In Bird:<br>> > neighbor fe80::2022:22ff:fe22:2201%ens13 external;<br>> > <br>> > But then the link local address doesn't work with multihop (for obvious<br>> > reason).<br>> > bird: /etc/bird/bird.conf:22:1 Multihop BGP cannot be used with link-local<br>> > addresses<br>> <br>> I use lladdrs for BGP endpoints in my network and that works fine. I think<br>> using `direct` instead of `multihop` in the v6-lladdr case would make it<br>> work for you.<br>> <br>> One word of advice: don't use the %scope syntax, use the `interface`<br>> directive instead. I don't recall exactly why but I had some subtle problem<br>> with that.<br>> <br>> As for your v4/32 problem, give `multihop 1` a try. That enforces no<br>> routers on the path to the peer like direct but allows off-subnet<br>> endpoints. Do keep in mind the docs recommend setting the source address<br>> explicitly when enabling multihop.<br><br>Hi<br><br>Note that using multihop fixes the issue with waiting for the address<br>range to appear, but there is still an issue with next hop resolution.<br>Multihop routes use recursive next hop resolution and in the case of /32<br>address ranges, there is no route for resolving neighbor IP announced as<br>next hop.<br><br>One would need a static route like:<br><br>route NBR-IP/32 via "IFACE";<br><br>So the next hop will be resolved.<br><br><br>Thinking about it, it makes sense to have something like direct mode that<br>works with unnumbered interfaces (or ones with /32 address).<br><br>-- <br>Elen sila lumenn' omentielvo<br><br>Ondrej 'Santiago' Zajicek (email: <a href="mailto:santiago@crfreenet.org" target="_blank">santiago@crfreenet.org</a>)<br>"To err is human -- to blame it on a computer is even more so."<o:p></o:p></p></blockquote></div><p class=MsoNormal><br clear=all><br><span class=gmailsignatureprefix>-- </span><o:p></o:p></p><div><div><div><div><div><p class=MsoNormal>Arzhel<o:p></o:p></p></div></div></div></div></div></div></body></html>