From: Balmik Soin (balmik@staff.iinet.net.au)
Date: Fri Nov 02 2007 - 21:31:03 ART
Cyrus,
It is necessary in certain circumstances. For instance if you're running
OSPFv3 in non-broadcast mode between R1, R2 and R5, when R2 receives
routes advertised from R5, they will have R5's link-local address as the
next-hop - if R2 does not have a mapping for that address, encapsulation
will fail to those destinations.
As a general rule, I always map the link-locals of spokes on other
spokes, just in case. It doesn't cause any harm.
- Balmik.
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
Of
> sirus MOGHADASIAN
> Sent: Saturday, 3 November 2007 7:30 AM
> To: Chris Riling
> Cc: Joseph Saad; groupstudy
> Subject: Re: is it necessary to map L3 to L2 add of IPv6 in
frame-relay
> spoke-to-spoke connection?
>
> Thanks all for answering but I think u misunderstand my question,
>
> My qustion was not why we use link-local address in ipv6 , the
question is
> why we need additional ipv6 link-local address,for example link-local
> address of R2 on R5?? I said I think if I map R1 link local address
on R5
> ,every think will be correct but why in some workbooks do additional
> mapping
> (R2 link local mapping in R5?? according to the fact that there is no
need
> that R5 and R2 become neighbor.
>
>
>
> Cyrus
>
> On 11/1/07, Chris Riling <criling@gmail.com> wrote:
> >
> > Yep... think about it... the v6 routing protocols use it for next
hop,
> and
> > you could have two v6 global unicast addresses on each side of a p2p
> link
> > that are in different subnets, and it *should* still work (haven't
> gotten
> > a
> > chance to lab it yet), because it uses link locals for communication
-
> it
> > took me a little while to get used to that... :)
> >
> > Chris
> >
> >
> > On 10/31/07, Joseph Saad <joseph.samir.saad@gmail.com> wrote:
> > >
> > > Also, to establish neighbors on NBMA networks, you'll need to
refer to
> > the
> > > neighbor's ipv6 link-local address. Which is, by the way, an
> > > interface-level
> > > command.
> > >
> > > On 11/1/07, Chris Riling <criling@gmail.com> wrote:
> > > >
> > > > The v6 protocols seem to like to use the link local addresses
for
> next
> > > > hop,
> > > > so I'd make sure there's a way for resolve the link locals...
Take a
> > > look
> > > > at
> > > > the v6 routing table when you get OSPF up and you'll see why you
> need
> > > > it...
> > > >
> > > > Chris
> > > >
> > > > On 10/31/07, hadek.el-ayachi@nsn.com <hadek.el-ayachi@nsn.com>
wrote:
> > > > >
> > > > > You need this when running ospf in hub-and-spoke topology
using
> > > > > broadcast or non-broacast network type. Match like ipv4.
> > > > >
> > > > >
> > > > > -----Original Message-----
> > > > > From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On
> Behalf
> > > Of
> > > > > ext sirus MOGHADASIAN
> > > > > Sent: mercredi 31 octobre 2007 14:44
> > > > > To: Cisco certification
> > > > > Subject: is it necessary to map L3 to L2 add of IPv6 in frame-
> relay
> > > > > spoke-to-spoke connection?
> > > > >
> > > > > Hi Gs,
> > > > >
> > > > > R5 ------R1---------R2
> > > > >
> > > > > R1 ,R2 ,R5 run frame-relay on their main serial interface.
> > > > >
> > > > > I ran Ipv6 and Ripng on them.
> > > > >
> > > > > I have v6 routes is each routers table
> > > > >
> > > > > R5:
> > > > >
> > > > > interface Serial1/0
> > > > >
> > > > > ipv6 address 2001:CC1E:1:125::5/64
> > > > > ipv6 address FE80::5 link-local
> > > > > ipv6 rip 1 enable
> > > > > frame-relay map ipv6 FE80::CE00:15FF:FE2C:0 501
> > broadcast frame-relay
> > > > > map ipv6 2001:CC1E:1:125::1 501 broadcast frame-relay map
ipv6
> > > > > 2001:CC1E:1:125::2 501 broadcast
> > > > >
> > > > >
> > > > >
> > > > > R1 :
> > > > >
> > > > > interface Serial1/0
> > > > > ipv6 address 2001:CC1E:1:125::1/64
> > > > > ipv6 address FE80::1 link-local
> > > > > ipv6 rip 1 enable
> > > > > frame-relay map ipv6 FE80::CE01:15FF:FE2C:0 102
> > broadcast frame-relay
> > > > > map ipv6 FE80::CE04:15FF:FE2C:0 105 broadcast frame-relay map
> ipv6
> > > > > 2001:CC1E:1:125::2 102 broadcast frame-relay map ipv6
> > > > > 2001:CC1E:1:125::5 105 broadcast
> > > > >
> > > > >
> > > > > R2 :
> > > > >
> > > > > interface Serial1/0
> > > > > ipv6 address 2001:CC1E:1:125::2/64
> > > > > ipv6 address FE80::2 link-local
> > > > > ipv6 rip 1 enable
> > > > > frame-relay map ipv6 FE80::CE00:15FF:FE2C:0 201
> > broadcast frame-relay
> > > > > map ipv6 2001:CC1E:1:125::1 201 broadcast frame-relay map
ipv6
> > > > > 2001:CC1E:1:125::5 201 broadcast
> > > > >
> > > > >
> > > > >
> > > > > Question is : Is there any nedd to L3 to L2 link-local mapping
for
> > R2
> > > on
> > > > > R5 s1/0 ??? I see this solution with L3 to L2 mapping in some
> > > > > workbooks.
> > > > >
> > > > > As I said every thing is right ,I think this L3->L2 mapping
will
> be
> > > > > redundant.
> > > > >
> > > > >
> > > > > any idea?
> > > > >
> > > > >
> > > > > Cyrus
> > > > >
> > > > >
> > >
>
This archive was generated by hypermail 2.1.4 : Sat Dec 01 2007 - 06:37:27 ART