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RE: BGP with link-local addresses posted 01/12/2007
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I did not configure the link local addresses (I only did IPv6 enable under the
interfaces and configured a loopback on each router, with global addresses to
test that indeed updates were going across) The router picked his own IPv6
address based on MACs for the serial interface.  I think the key is the update
source command since the link local address as you said is unique. So, I don't
think you have to configure link local address unless asked to do so.

Regards,

Yasmin

________________________________

From: nobody@xxxxxxxxxxxxxx on behalf of Bit Gossip
Sent: Fri 1/12/2007 3:24 AM
To: ccielab@xxxxxxxxxxxxxx
Subject: Re: BGP with link-local addresses



Jim, Lara,
thank you for the big help: indeed your configs works also in my lab.
The big difference is that you have configured an explicit and unique
link-local address on the interface and this makes a difference!
In my original configuration I didn't configure a link-local address and
so the IOS assigned one based on a mac-address of the router.
Debugging IPv6 packets, I have noticed that the router can
not source pkts from such serial links complaining with 'invalid source
address'.
Maybe because it is not unique??? Anyway configuring a unique link-local
address makes the difference!
A bug or a feature ? Certainly not a BGP problem....

Shall we draw the conclusion: "Always configure a unique link-local
address on serial interfaces if need to use them" ?
Thanks,
Luca.


On Fri, 2007-01-12 at 06:39, Jim wrote:
> I don't have any problem using the link-local address, please see
> config below.
>
> r1:
> ipv6 unicast-routing
> interface Loopback0
>  ip address 2.2.1.1 255.255.255.0
> !
> interface Serial0/0.1 point-to-point
>  ipv6 address FEC0::2/64
>  ipv6 address FE80::1 link-local
>  frame-relay interface-dlci 201
> !
> router bgp 1
>  no synchronization
>  bgp log-neighbor-changes
>  neighbor FE80::2 remote-as 2
>  neighbor FE80::2 update-source Serial0/0.1
>  no neighbor FE80::2 activate
>  no auto-summary
>  !
>  address-family ipv6
>  neighbor FE80::2 activate
>  exit-address-family
> !
>
> ####
> r2:
> ipv6 unicast-routing
> interface Serial0/0.1 point-to-point
>  ipv6 address FEC0::1/64
>  ipv6 address FE80::2 link-local
>  frame-relay interface-dlci 210
> !
> router bgp 2
>  no synchronization
>  bgp log-neighbor-changes
>  neighbor FE80::1 remote-as 1
>  neighbor FE80::1 update-source Serial0/0.1
>  no neighbor FE80::1 activate
>  no auto-summary
>  !
>  address-family ipv6
>  neighbor FE80::1 activate
>  exit-address-family
>
>
> ### show output
> r1:
> # show bgp ipv6 summ
> BGP router identifier 2.2.1.1, local AS number 1
> BGP table version is 1, main routing table version 1
>
> Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down
> State/PfxRcd
> FE80::2         4     2       5       5        1    0    0
> 00:02:22        0
>
>
> r1(config)#do sh bgp ipv6 summ
> BGP router identifier 2.2.1.1, local AS number 1
> BGP table version is 1, main routing table version 1
>
> Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down
> State/PfxRcd
> FE80::2         4     2       5       5        1    0    0
> 00:02:22        0
> % NOTE: This command is deprecated. Please use 'show bgp ipv6 unicast'
>
> r1(config)#do sh bgp ipv6 uni nei
> BGP neighbor is FE80::2,  remote AS 2, external link
>  ...
> Connection state is ESTAB, I/O status: 1, unread input bytes:
> 0
> Connection is ECN Disabled, Mininum incoming TTL 0, Outgoing TTL 1
> Local host: FE80::1, Local port: 15843
> Foreign host: FE80::2, Foreign port: 179
>
>
> r2(config-router-af)#do show bgp ipv6 uni summ
> BGP router identifier 2.2.13.2, local AS number 2
> BGP table version is 1, main routing table version 1
>
> Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down
> State/PfxRcd
> FE80::1         4     1      11      11        1    0    0
> 00:08:46        0
> r2(config-router-af)#do show bgp ipv6 uni nei
> BGP neighbor is FE80::1,  remote AS 1, external link
> ...
> Connection state is ESTAB, I/O status: 1, unread input bytes: 0
> Connection is ECN Disabled
> Local host: FE80::2, Local port: 179
> Foreign host: FE80::1, Foreign port: 15843
>
>
> On 1/11/07, Bit Gossip <bit.gossip@xxxxxxxxx> wrote:
>         Group,
>         there is no way I can bring up a BGP session using IPv6
>         link-local
>         addresses over a point-point FR link. Same story for a GRE
>         tunnel.
>         While it works fine over a ethernet connection.
>
>         I noticed that even if I can ping the link-local address of
>         the peer, I
>         can not telnet it; maybe this is the problem.
>
>         Did someone succeeded in this task?
>
>         Thanks,
>         Luca
>
>
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