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    Announcing /48 to BGP peer

    Scheduled Pinned Locked Moved IPv6
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    • 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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