This is my try at documenting the just added add-path bits. -- :wq Claudio
Index: bgpd.8 =================================================================== RCS file: /cvs/src/usr.sbin/bgpd/bgpd.8,v retrieving revision 1.74 diff -u -p -r1.74 bgpd.8 --- bgpd.8 28 Jun 2022 11:52:24 -0000 1.74 +++ bgpd.8 11 Jul 2022 13:22:05 -0000 @@ -401,6 +401,16 @@ has been started. .Re .Pp .Rs +.%A D. Walton +.%A A. Retana +.%A E. Chen +.%A J. Scudder +.%D July 2016 +.%R RFC 7911 +.%T Advertisement of Multiple Paths in BGP +.Re +.Pp +.Rs .%A C. Petrie .%A T. King .%D May 2017 Index: bgpd.conf.5 =================================================================== RCS file: /cvs/src/usr.sbin/bgpd/bgpd.conf.5,v retrieving revision 1.223 diff -u -p -r1.223 bgpd.conf.5 --- bgpd.conf.5 28 Jun 2022 11:52:24 -0000 1.223 +++ bgpd.conf.5 11 Jul 2022 14:08:24 -0000 @@ -843,6 +843,57 @@ The default is .Ic no . .Pp .It Xo +.Ic announce add-path send +.Pq Ic no Ns | Ns Ic all +.Xc +.It Xo +.Ic announce add-path send +.Pq Ic best Ns | Ns Ic ecmp | Ns Ic as-wide-best +.Op Ic plus Ar num +.Op Ic max Ar num +.Xc +If set to +.Ic all , +.Ic best , +.Ic ecmp , +or +.Ic as-wide-best , +the send add-path capability is announced which allows to send multiple paths +per prefix. +Which paths are sent depends on the mode: +.Pp +.Bl -tag -width as-wide-best -compact +.It Ic all +send all valid prefixes +.It Ic best +send the best prefix and maybe more +.It Ic ecmp +send prefixes with equal nexthop cost +.It Ic as-wide-best +send prefixes where the fist 8 check of the decision process match +.El +.Pp +.Ic plus +allows to include additional routes and works for +.Ic best , +.Ic ecmp , +and +.Ic as-wide-best . +.Ic max +can be used to limit the total amount of routes announced for +.Ic ecmp +and +.Ic as-wide-best . +The default is +.Ic no . +.Pp +Right now +.Ic ecmp +and +.Ic as-wide-best +are equivalent. +.Pp +.It Xo .Ic announce as-4byte .Pq Ic yes Ns | Ns Ic no .Xc
