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    Announcing /48 to BGP peer

    Scheduled Pinned Locked Moved IPv6
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    • yon 0Y
      yon 0 @mrsunfire
      last edited by

      https://www.ripe.net/publications/docs/ripe-690

      johnpozJ 1 Reply Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator @yon 0
        last edited by johnpoz

        Yeah so.. What does that have to do with anything?

        The part where they say you should allocate a /48 to users? Completely agree - that has ZERO to do with putting a /48 on an interface.

        I have a /48 from HE for example.. Putting a /48 on interface would make all 65k of those 64's useless!

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
        Please don't Chat/PM me for help, unless mod related
        SG-4860 24.11 | Lab VMs 2.8, 24.11

        M 1 Reply Last reply Reply Quote 1
        • yon 0Y
          yon 0 @mrsunfire
          last edited by

          FRR v7.5.1 change to must setup /48 or above in Lan interface now, if the pfsense has no any interface setup /48 prefix, then ipv6
          lost normal work. i have been test frr7.5.1 in ubuntu 20..10 system get the same result.

          johnpozJ 1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator @yon 0
            last edited by

            @yon-0 said in IPv6 broken beyond pfSense after 2.5 upgrade:

            FRR v7.5.1 change to must setup /48 or above in Lan interface now

            Dude NO is doesn't... I am sorry you are not understanding how this works... But you DO NOT PUT a /48 on an interface - PERIOD!!

            An intelligent man is sometimes forced to be drunk to spend time with his fools
            If you get confused: Listen to the Music Play
            Please don't Chat/PM me for help, unless mod related
            SG-4860 24.11 | Lab VMs 2.8, 24.11

            yon 0Y 1 Reply Last reply Reply Quote 0
            • yon 0Y
              yon 0 @johnpoz
              last edited by

              @johnpoz

              Maybe I don't understand the theory, I just summarize the practical experience, if I run FRR7.5.1 then this happens. I just reflect the situation encountered.

              johnpozJ DerelictD 2 Replies Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator @yon 0
                last edited by

                Your not understanding how to setup a route without putting in on the interface??

                This goes same for IPv4... If have a /30 that connects 2 routers, are you saying I can not route a /8 through those? Or a /16 etc.. Because the network needs to be on the interface? How would routing ever work..

                An intelligent man is sometimes forced to be drunk to spend time with his fools
                If you get confused: Listen to the Music Play
                Please don't Chat/PM me for help, unless mod related
                SG-4860 24.11 | Lab VMs 2.8, 24.11

                1 Reply Last reply Reply Quote 0
                • DerelictD
                  Derelict LAYER 8 Netgate @yon 0
                  last edited by

                  @yon-0 The whole point of BGP is to announce routes that are reachable. If the route is not reachable, it will not be announced.

                  That does not mean that the only method of making a route reachable is to number an interface with it.

                  This is what you get when you simply add a network statement for a /48 without the route being reachable:

                  # show bgp ipv6
                  BGP table version is 5, local router ID is 172.25.232.1, vrf id 0
                  Default local pref 100, local AS 65001
                  Status codes:  s suppressed, d damped, h history, * valid, > best, = multipath,
                                 i internal, r RIB-failure, S Stale, R Removed
                  Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
                  Origin codes:  i - IGP, e - EGP, ? - incomplete
                  
                     Network          Next Hop            Metric LocPrf Weight Path
                  *> ::/0             fe80::bc7f:82ff:feea:ecf8
                                                               0         32768 ?
                     2001:470:beef::/48
                                      ::                       0         32768 i
                  
                  Displayed  2 routes and 2 total paths
                  

                  Note there is no * indicating a valid route. That means it will not be announced by BGP.

                  Now,

                  a5e00128-b11a-4537-96a3-62c6b1707f68-image.png

                  Now it is both active * and best > and announced to the peer

                  Codes: K - kernel route, C - connected, S - static, R - RIPng,
                         O - OSPFv3, I - IS-IS, B - BGP, N - NHRP, T - Table,
                         v - VNC, V - VNC-Direct, A - Babel, D - SHARP, F - PBR,
                         f - OpenFabric,
                         > - selected route, * - FIB route, q - queued, r - rejected, b - backup
                  
                  K>* ::/0 [0/0] via fe80::bc7f:82ff:feea:ecf8, lo0, 00:01:15
                  S>* 2001:470:beef::/48 [1/0] unreachable (blackhole), weight 1, 00:01:15
                  
                  vtysh# show bgp ipv6 neighbors 172.25.228.58 advertised-routes 
                  BGP table version is 3, local router ID is 172.25.232.1, vrf id 0
                  Default local pref 100, local AS 65001
                  Status codes:  s suppressed, d damped, h history, * valid, > best, = multipath,
                                 i internal, r RIB-failure, S Stale, R Removed
                  Nexthop codes: @NNN nexthop's vrf id, < announce-nh-self
                  Origin codes:  i - IGP, e - EGP, ? - incomplete
                  
                     Network          Next Hop            Metric LocPrf Weight Path
                  *> ::/0             ::                       0         32768 ?
                  *> 2001:470:beef::/48
                                      ::                       0         32768 ?
                  

                  I sent that traffic to Null/Blackhole but if there are any longer prefixes (like /64 interface routes) they will be the preferred route for that traffic. It also has a status of unreachable because it is a null route but BGP is coerced into announcing it.

                  Chattanooga, Tennessee, USA
                  A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                  DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                  Do Not Chat For Help! NO_WAN_EGRESS(TM)

                  M yon 0Y 2 Replies Last reply Reply Quote 1
                  • yon 0Y
                    yon 0 @Derelict
                    last edited by

                    @derelict

                    I had used /48 in pf 2.4.5 and pf 2.5beta was
                    normal work.

                    L DerelictD 2 Replies Last reply Reply Quote 0
                    • L
                      lnguyen @yon 0
                      last edited by

                      @yon-0 You share one bit in common with a /48, quite dense.

                      1 Reply Last reply Reply Quote 0
                      • DerelictD
                        Derelict LAYER 8 Netgate @yon 0
                        last edited by

                        @yon-0 said in IPv6 broken beyond pfSense after 2.5 upgrade:

                        @derelict

                        I had used /48 in pf 2.4.5 and pf 2.5beta was
                        normal work.

                        It is going to be very difficult to get developer time to "fix" something in what amounts to a nonsensical configuration.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

                        johnpozJ 1 Reply Last reply Reply Quote 1
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @Derelict
                          last edited by

                          Why stop there.. While they are at - let me put a /32 on the interface.. That is the min sized prefix you get from arin ;) so you might as well let me put it on my interface - I might want to route it <rolleyes>

                          And clearly the only way to route anything is put it on an interface..

                          An intelligent man is sometimes forced to be drunk to spend time with his fools
                          If you get confused: Listen to the Music Play
                          Please don't Chat/PM me for help, unless mod related
                          SG-4860 24.11 | Lab VMs 2.8, 24.11

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