Hello  - This problem persisted right up until today/yesterday, a day after sbourque contacted me.  He runs a similar cfg with the same vendors and has the same problem.  When he contacted me I had the same hardware and cfg and the same problem as when I posted this in April. We have had an ASR waiting to replace this 7201 and had the opportunity to replace it last night. I copied the cfg line for line from the 7201 to the ASR 1002 with only some interface name changes and it functions as expected on the ASR. The IPv6 on both sub interfaces now functions as desired, neighbour discovery worked, and the IPv6 protocol came up. As soon as we figure out why/how I'll share it here.  7201 was running a 12.4.(4) and the ASR is running a 15.1 version. Steve ... View more

Phillip - I like that idea of putting an additional device on line in the path.  I'm going to ask the RAN/carrier to put a device on the vlan mid way and see which, if either end they can see. thanks for the idea steve ... View more

Hello Phillip Thanks for the ideas.  No I cannot ping the IPS B interface over IPv6, same link and sub-interface with IPv4 pings fine.  PING was my first attempt, and when it didn't ping I went to see if it had formed a neighbor relationship on the link, and it hadn't. Yes, it does look like a unidirectional link, or FW issuse but there in no FW or ACLs in place on the link between the 2 sites.  ISP B is on a vlan/subinterface on my end, carried by a RAN to a demarc, and broken out onto a switch accessport to connect to ISP B's physical interface.  I{v4 traffic to ISP B on the same sub-interface is fine. Steve ... View more

Alain - thanks for giving this some thought - I've been scratching my head on this. I'll update the link as we make progress on it Steve ... View more

I tried forcing the link-local address with these two commands to see if that made a differnce I tried this one first - ipv6 address fe80::227:dff:fe8a:a917 link-local then I tried this one - ipv6 address fe80::227:dff:fe11:1111 link-local in both cases the interface also had these two lines ipv6 address 2001:550:2:8::2:2/112 ipv6 enable after disabe and enable ipv6 on the interface the out of sho int was BA-B227-RO01#sho ipv6 int brief FastEthernet0/0            [up/up] GigabitEthernet0/0         [administratively down/down] GigabitEthernet0/1         [administratively down/down] GigabitEthernet0/2         [up/up] GigabitEthernet0/2.1       [administratively down/down] GigabitEthernet0/2.50      [up/up]     FE80::227:DFF:FE9A:A919     2620:DD::1:0:0:1 GigabitEthernet0/3         [up/up] GigabitEthernet0/3.252     [up/up]     unassigned GigabitEthernet0/3.552     [up/up]     FE80::227:DFF:FE11:1111     2001:550:2:8::2:2 GigabitEthernet0/3.752     [up/up]     FE80::227:DFF:FE9A:A917     2607:FD78:302:1::2 FastEthernet1/0            [administratively down/down] BA-B227-RO01# and the sho ipv6 nei comamnd still shows no neibour relationship with the remote end BA-B227-RO01# BA-B227-RO01#sho ipv6 nei IPv6 Address                              Age Link-layer Addr State Interface FE80::226:51FF:FECA:A4D3                    0 0026.51ca.a4d3  DELAY Gi0/3.752 2001:550:2:8::2:1                           0 001d.e511.6000  DELAY Gi0/3.552 2607:FD78:302:1::1                          0 0026.51ca.a4d3  REACH Gi0/3.752 FE80::250:56FF:FE80:3506                    0 0050.5680.3506  REACH Gi0/2.50 2620:DD::250:56FF:FE80:3506                 0 0050.5680.3506  DELAY Gi0/2.50 BA-B227-RO01# attached is debug ipv6 nd output ... View more

I've attached a larger about as a file, see atatched but the line of interest is this one I believe Apr 14 14:39:27.508: BGP: 2001:550:2:8::2:1 open failed: Connection timed out; remote host not responding, open active delayed 32928ms (35000ms max, 28% jitter) which I believe points back to the lack of IPv6 conenctivity to that site.  I should mention that I can not ping the 2001:55:2:8::2:1 address on the other end which led me to the IPv6 neighbour issue.  IPv4 is operatinal and fine on this same link and vlan. in the previous debug'ing I can see the remote end and my end trying to establish ipv6 neighbour relationship but it never completes.  It simply cycles from not being in the neighbour table, to status PROBE, DELAY or INCMP thanks steve ... View more

Hello In looking at the output of the sho ipv6 interface commands, is the issue that both of the sub-interfaces generated the same link-local address since they are on the same physical link ? BA-B227-RO01#sho ipv6 nei IPv6 Address                              Age Link-layer Addr State Interface FE80::226:51FF:FECA:A4D3                    0 0026.51ca.a4d3  REACH Gi0/3.752 2001:550:2:8::2:1                           0 001d.e511.6000  PROBE Gi0/3.552 2607:FD78:302:1::1                          0 0026.51ca.a4d3  REACH Gi0/3.752 FE80::250:56FF:FE80:3506                    0 0050.5680.3506  DELAY Gi0/2.50 2620:DD::250:56FF:FE80:3506                 0 0050.5680.3506  REACH Gi0/2.50 BA-B227-RO01#sho ipv6 int gi0/3.552 GigabitEthernet0/3.552 is up, line protocol is up   IPv6 is enabled, link-local address is FE80::227:DFF:FE9A:A917   No Virtual link-local address(es): BA-B227-RO01#sho ipv6 int gi0/3.752 GigabitEthernet0/3.752 is up, line protocol is up   IPv6 is enabled, link-local address is FE80::227:DFF:FE9A:A917   No Virtual link-local address(es): I never see a link local address in the neighbour table for the gi0/3.552 sub-i/f, only the gi0/3.752 sub-i/f Is there a way to bind a virtual link local address to the i/f - or is it simply a regualr assignemnt with an fe80 address ? what woudl happen if I bound an IPv6 address to the physical link, woudl I then possiby loose the assignemnt and operation on the gi0/3.752 since there woudl noe bw 3 i/fs trying to use same link-local address ? thanks steve ... View more

As suggested, please see the output from the various sho comamnds below BA-B227-RO01#sho run | sec bgp router bgp 19764 bgp log-neighbor-changes neighbor 2001:550:2:8::2:1 remote-as 174 neighbor 2607:FD78:302:1::1 remote-as 26677 neighbor 38.107.139.89 remote-as 174 neighbor 38.107.139.89 description Cogent's A Peer to BA router neighbor 38.107.139.89 password 7 xxxxxxxxxxxxxxxxxx neighbor 66.97.23.205 remote-as 26677 neighbor 66.97.23.205 description ORION - Advanced R&E Peer neighbor 66.97.23.205 password 7 xxxxxxxxxxxxxxxxxxxxxxxxxxx neighbor 66.209.49.13 remote-as 30147 neighbor 66.209.49.13 description ***Atria_Networks*** neighbor 66.209.49.13 password 7 xxxxxxxxxxxxxxxxxxxxxx neighbor 66.209.49.13 timers 20 60 maximum-paths 6 ! address-family ipv4 redistribute static no neighbor 2001:550:2:8::2:1 activate no neighbor 2607:FD78:302:1::1 activate neighbor 38.107.139.89 activate neighbor 38.107.139.89 route-map COGENT-out out neighbor 66.97.23.205 activate neighbor 66.97.23.205 send-community neighbor 66.97.23.205 prefix-list GC_Routes_out out neighbor 66.97.23.205 route-map ORION-OUT out neighbor 66.209.49.13 activate neighbor 66.209.49.13 default-originate neighbor 66.209.49.13 advertisement-interval 20 neighbor 66.209.49.13 prefix-list GC_Routes_out out neighbor 66.209.49.13 route-map ATRIA-OUT out maximum-paths 6 no auto-summary no synchronization network 192.139.153.16 mask 255.255.255.240 network 198.73.133.0 network 198.73.134.0 network 199.212.2.0 aggregate-address 192.139.153.0 255.255.255.0 summary-only exit-address-family ! address-family ipv6 neighbor 2001:550:2:8::2:1 activate neighbor 2001:550:2:8::2:1 prefix-list GC_IPv6_routes_out out neighbor 2607:FD78:302:1::1 activate neighbor 2607:FD78:302:1::1 prefix-list GC_IPv6_routes_out out network 2620:DD::/48 exit-address-family ! address-family nsap maximum-paths 6 no synchronization exit-address-family snmp-server enable traps bgp BA-B227-RO01# BA-B227-RO01#sho ipv6 int gi0/3.552 GigabitEthernet0/3.552 is up, line protocol is up   IPv6 is enabled, link-local address is FE80::227:DFF:FE9A:A917   No Virtual link-local address(es):   Description: "Cogent Internet service"   Global unicast address(es):     2001:550:2:8::2:2, subnet is 2001:550:2:8::2:0/112   Joined group address(es):     FF02::1     FF02::2     FF02::1:FF02:2     FF02::1:FF9A:A917   MTU is 1500 bytes   ICMP error messages limited to one every 100 milliseconds   ICMP redirects are enabled   ICMP unreachables are sent   ND DAD is enabled, number of DAD attempts: 1   ND reachable time is 30000 milliseconds   ND advertised reachable time is 0 milliseconds   ND advertised retransmit interval is 0 milliseconds   ND router advertisements are sent every 200 seconds   ND router advertisements live for 1800 seconds   ND advertised default router preference is Medium   Hosts use stateless autoconfig for addresses. BA-B227-RO01# BA-B227-RO01#sho bgp ipv6 uni sum BGP router identifier 38.103.65.233, local AS number 19764 BGP table version is 101437, main routing table version 101437 5304 network entries using 790296 bytes of memory 5304 path entries using 403104 bytes of memory 66900/3881 BGP path/bestpath attribute entries using 8295600 bytes of memory 58695 BGP AS-PATH entries using 1590222 bytes of memory 186 BGP community entries using 5752 bytes of memory 0 BGP route-map cache entries using 0 bytes of memory 0 BGP filter-list cache entries using 0 bytes of memory BGP using 11084974 total bytes of memory BGP activity 8971318/8617212 prefixes, 12341444/11976395 paths, scan interval 60 secs Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd 2001:550:2:8::2:1                 4   174       0       0        0    0    0 never    Active 2607:FD78:302:1::1                 4 26677   98859   11064   101437    0    0 1w0d         5303 BA-B227-RO01# BA-B227-RO01#sho ip bgp ipv6 unicast nei BGP neighbor is 2001:550:2:8::2:1,  remote AS 174, external link   BGP version 4, remote router ID 0.0.0.0   BGP state = Active   Last read 1w0d, last write 1w0d, hold time is 180, keepalive interval is 60 seconds   Message statistics:     InQ depth is 0     OutQ depth is 0                          Sent       Rcvd     Opens:                  0          0     Notifications:          0          0     Updates:                0          0     Keepalives:             0          0     Route Refresh:          0          0     Total:                  0          0   Default minimum time between advertisement runs is 30 seconds For address family: IPv6 Unicast   BGP table version 101454, neighbor version 0/0 Output queue size : 0   Index 1, Offset 0, Mask 0x2   1 update-group member   Outgoing update prefix filter list is GC_IPv6_routes_out                                  Sent       Rcvd   Prefix activity:               ----       ----     Prefixes Current:               1          0     Prefixes Total:                 0          0     Implicit Withdraw:              0          0     Explicit Withdraw:              0          0     Used as bestpath:             n/a          0     Used as multipath:            n/a          0                                    Outbound    Inbound   Local Policy Denied Prefixes:    --------    -------     Total:                                0          0   Number of NLRIs in the update sent: max 0, min 0   Connections established 0; dropped 0   Last reset never   No active TCP connection BGP neighbor is 2607:FD78:302:1::1,  remote AS 26677, external link   BGP version 4, remote router ID 66.97.18.19   BGP state = Established, up for 1w0d   Last read 00:00:10, last write 00:00:00, hold time is 180, keepalive interval is 60 seconds   Neighbor capabilities:     Route refresh: advertised and received(old & new)     Address family IPv6 Unicast: advertised and received   Message statistics:     InQ depth is 0     OutQ depth is 0                          Sent       Rcvd     Opens:                  1          1     Notifications:          0          0     Updates:                1      98866     Keepalives:         11064         11     Route Refresh:          0          0     Total:              11066      98878   Default minimum time between advertisement runs is 30 seconds For address family: IPv6 Unicast   BGP table version 101454, neighbor version 101451/0 Output queue size : 0   Index 1, Offset 0, Mask 0x2   1 update-group member   Outgoing update prefix filter list is GC_IPv6_routes_out                                  Sent       Rcvd   Prefix activity:               ----       ----     Prefixes Current:               1       5301 (Consumes 402876 bytes)     Prefixes Total:                 1     109971     Implicit Withdraw:              0      97857     Explicit Withdraw:              0       6813     Used as bestpath:             n/a       5301     Used as multipath:            n/a          0                                    Outbound    Inbound   Local Policy Denied Prefixes:    --------    -------     prefix-list                       94493          0     Suppressed duplicate:                 0      15332     AS_PATH loop:                       n/a          1     Bestpath from this peer:           5270        n/a     Total:                            99763      15333   Number of NLRIs in the update sent: max 1, min 1   Connections established 1; dropped 0   Last reset never Connection state is ESTAB, I/O status: 1, unread input bytes: 0 Connection is ECN Disabled Local host: 2607:FD78:302:1::2, Local port: 32189 Foreign host: 2607:FD78:302:1::1, Foreign port: 179 Connection tableid (VRF): 0 Enqueued packets for retransmit: 0, input: 0  mis-ordered: 0 (0 bytes) Event Timers (current time is 0x5949ADC24): Timer          Starts    Wakeups            Next Retrans         11066          1             0x0 TimeWait            0          0             0x0 AckHold         22948      17433             0x0 SendWnd             0          0             0x0 KeepAlive           0          0             0x0 GiveUp              0          0             0x0 PmtuAger            0          0             0x0 DeadWait            0          0             0x0 Linger              0          0             0x0 iss: 2274602483  snduna: 2274812833  sndnxt: 2274812833     sndwnd:  31856 irs: 3457516074  rcvnxt: 3467046155  rcvwnd:      15202  delrcvwnd:   1182 SRTT: 300 ms, RTTO: 303 ms, RTV: 3 ms, KRTT: 0 ms minRTT: 0 ms, maxRTT: 1668 ms, ACK hold: 200 ms Status Flags: active open Option Flags: nagle IP Precedence value : 6 Datagrams (max data segment is 1440 bytes): Rcvd: 34705 (out of order: 0), with data: 23595, total data bytes: 9530080 Sent: 34487 (retransmit: 1, fastretransmit: 0, partialack: 0, Second Congestion: 0), with data: 34487, total data bytes: 1589837 BA-B227-RO01# ... 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