From: shiran guez (shiranp3@gmail.com)
Date: Thu Dec 13 2007 - 04:57:43 ART
Bad Design usually can lead to Network Problem. you are correct that there
is no explicit deny on putting the neighbour statement in either the spoke
or the hub, but Cisco probably did that as a protection against Bad Design.
also I do not see a real reason why you want to go to each spoke and do it
on them instead of putting it on the central hub, less overhead and more
organized.
On Dec 13, 2007 9:32 AM, Alan Ewer <acewer64@gmail.com> wrote:
> Hi .
> I know and understand what you are trying to say but still doesnt explain
> to my satisfaction why the neighbour command cannot be on the spokes.
> (except to maybe prevent against misconfiguring NON-DR/BDR -> NON DR/BDR
> adjacencies). The neighbour command only seems to be used to INITIATE
> communications ..to ultimately form adjacency..
>
> So really should it matter where the adjacency is initiated from... why
> cant it be the spoke.??
>
>
> ie if the DR and BDR are already defined ( maybe ip ospf priority 100 and
> 200 are set on other routers )
> then why not use neighbour commands on the spokes. Since this router is
> not going to be DR or BDR ...isnt that the same as applying the ip ospf
> priority 0 to this router ??
>
> As i said , and George ( i think) pointed out it maybe Cisco preventing
> misconfigurations like the one i have lready pointed out.. other than that
> there is no reason why iot cannot be on the spokes except Cisco have it as a
> safeguard feature , rather than a limitation of OSPF .. if you get my point
> ..
>
> Thanks for the input all.
> Alan E
> Brisbane
>
>
> On 12/13/07, shiran guez <shiranp3@gmail.com> wrote:
> >
> > A neighbour statement should be on the hub as the Hub is the connector
> > between the spokes and not the other way around if a spoke go down none of
> > the other spokes will be effected but if the Hub go down all the spokes will
> > loose communication so the logic is that due to the fact that the Hub is
> > keeping all the spokes together the Hub should be the place where you
> > initiate connection to the spokes and you do that by putting the neighbour
> > statement under the Hub ospf process.
> >
> > Think of the Job that DR and BDR have, they are listening to there
> > Neighbour LSA and updating the Area about the Database to be sync so if you
> > say under the process to unicast a neighbor it mean that you want to update
> > him with LSA, but you also say that you are not the DR/BDR and never will be
> > then you actually can jeopardise the concept of DR/BDR as if you try to
> > neighbor with another non DR/BDR you will start exchanging LSA on NBMA when
> > it is the Job of the DR to update you.
> >
> >
> > I hope it is not a total mess but try to think of the DR/BDR job
> > prospective and you realize that it is Bad Design to put the neighbour on
> > the spoke.
> >
> > On Dec 12, 2007 11:53 PM, Alan Ewer <acewer64@gmail.com> wrote:
> >
> > > Hi guys..
> > > Yes I disagree that its not required.. A neighbour command must be
> > > configured somewhere, why not on the spokes ? Maybe a hole in my
> > > understanding of OSPF NBMA but it shouldnt matter where the neighbour
> > > command is as long as someone statrs the adjacency negotiation... all is
> > > good ....correct ??
> > >
> > > Regds
> > > Alan E
> > > Brisbane Australia
> > >
> > >
> > > On Dec 13, 2007 6:07 AM, shiran guez <shiranp3@gmail.com> wrote:
> > >
> > > > nice :-)
> > > >
> > > >
> > > >
> > > >
> > > > On Dec 12, 2007 10:03 PM, George Goglidze <goglidze@gmail.com>
> > > > wrote:
> > > >
> > > > > Hi Shiran,
> > > > >
> > > > > That is what happens until you restart your router!!! :)))
> > > > >
> > > > > try restart it with priority 0, and you'll see that after it comes
> > > > > up,
> > > > > even if you change your priority the neighbor statement is not
> > > > > there any more...
> > > > >
> > > > > Regards,
> > > > >
> > > > >
> > > > >
> > > > > On Dec 12, 2007 8:45 PM, shiran guez <shiranp3@gmail.com> wrote:
> > > > >
> > > > > > George
> > > > > >
> > > > > > try to set it up with the ip ospf prio 0 and the neigbor
> > > > > > statement under the ospf process and then only remove the ip ospf prio 0,
> > > > > > you will see that your neighbor statement is reappearing so it indicate that
> > > > > > it is only hidden and not removed.
> > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > On Dec 12, 2007 6:15 PM, George Goglidze <goglidze@gmail.com>
> > > > > > wrote:
> > > > > >
> > > > > > > Hi there,
> > > > > > >
> > > > > > > It's not hidden, it's simply removed as it's not needed.
> > > > > > >
> > > > > > > when you have NBMA network and you set priority 0 on non-hub
> > > > > > > routers.
> > > > > > > the neighbor command is removed on next reload.
> > > > > > >
> > > > > > > I'm not sure, but I think this could be security against
> > > > > > > misconfiguration,
> > > > > > > so that you don't configure non-hub -to- non-hub neighbor.
> > > > > > >
> > > > > > > in NBMA mode you just configure neighbor on DR and BDR.
> > > > > > >
> > > > > > > that's the only neighborship you need anyway.
> > > > > > >
> > > > > > > Regards,
> > > > > > >
> > > > > > > On Dec 12, 2007 4:21 PM, shiran guez <shiranp3@gmail.com>
> > > > > > > wrote:
> > > > > > >
> > > > > > >
> > > > > > > > the command is hidden not gone, i do not think it is a bug
> > > > > > > > but as I said
> > > > > > > > before a issue of cosmetics.
> > > > > > > >
> > > > > > > > On Dec 12, 2007 4:40 PM, keith tokash < ktokash@hotmail.com >
> > > > > > > > wrote:
> > > > > > > >
> > > > > > > > > Can you test if the command is hidden or simply gone?
> > > > > > > > Easy way to do this
> > > > > > > > > is to remove the neighbor command from the hub and see if
> > > > > > > > the neighbors come
> > > > > > > > > up.
> > > > > > > > >
> > > > > > > > > If there's a valid reason for this I want to know. If
> > > > > > > > it's a bug, we may
> > > > > > > > > hit it in the lab, and I also want to know. :)
> > > > > > > > >
> > > > > > > > > With a few exceptions, secrecy is deeply incompatible with
> > > > > > > > democracy and
> > > > > > > > > with science.
> > > > > > > > > --Carl Sagan
> > > > > > > > >
> > > > > > > > > > Date: Wed, 12 Dec 2007 14:03:56 +0200
> > > > > > > > > > From: shiranp3@gmail.com
> > > > > > > > > > To: acewer64@gmail.com
> > > > > > > > > > Subject: Re: OSPF Neighbour config wont stick in config
> > > > > > > > ?
> > > > > > > > > > CC: ccielab@groupstudy.com
> > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > well I would say that logically it doesn't make sense to
> > > > > > > > put there in
> > > > > > > > > the
> > > > > > > > > > first place so the developers probably made it to be
> > > > > > > > hidden when you put
> > > > > > > > > the
> > > > > > > > > > interface into prio 0
> > > > > > > > > >
> > > > > > > > > > if you will remove the ip os prio 0 you will see again
> > > > > > > > your neighbor
> > > > > > > > > > statement so it was not remove simply hidden to hint you
> > > > > > > > that it is not
> > > > > > > > > > needed, so it is just cosmetics.
> > > > > > > > > >
> > > > > > > > > > On Dec 12, 2007 1:01 PM, Alan Ewer < acewer64@gmail.com>
> > > > > > > > wrote:
> > > > > > > > > >
> > > > > > > > > > > Hi Shiren,
> > > > > > > > > > > yes i understand that the neighbour command can be on
> > > > > > > > either location
> > > > > > > > > (
> > > > > > > > > > > but doesnt need to be on both)..
> > > > > > > > > > >
> > > > > > > > > > > My Question is
> > > > > > > > > > > Why does setting ip ospf pri 0 .. remove the neighbour
> > > > > > > > command from
> > > > > > > > > the
> > > > > > > > > > > ospf process configuration ??
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > > Regds
> > > > > > > > > > > Alan E
> > > > > > > > > > >
> > > > > > > > > > > On Dec 12, 2007 8:53 PM, shiran guez <
> > > > > > > > shiranp3@gmail.com> wrote:
> > > > > > > > > > >
> > > > > > > > > > > > you do not need a neighbor statement on the spoke of
> > > > > > > > the hub. only
> > > > > > > > > on
> > > > > > > > > > > > the hub.
> > > > > > > > > > > >
> > > > > > > > > > > > if you set ip ospf prio 0 this router will never
> > > > > > > > become a DR or BDR
> > > > > > > > > so
> > > > > > > > > > > > no need to indicate where to unicast
> > > > > > > > > > > >
> > > > > > > > > > > > On Dec 12, 2007 12:38 PM, Alan Ewer < acewer64@gmail.com
> > > > > > > > > wrote:
> > > > > > > > > > > >
> > > > > > > > > > > > > Hi All
> > > > > > > > > > > > > I have been pondering this little brain teaser ??
> > > > > > > > > > > > >
> > > > > > > > > > > > > If I have a router configured with the following
> > > > > > > > > > > > >
> > > > > > > > > > > > > router ospf 1
> > > > > > > > > > > > > router id 1.1.1.1
> > > > > > > > > > > > > network 1.1.1.0 0.0.0.255 AREA 0
> > > > > > > > > > > > > neighbour 1.1.1.2
> > > > > > > > > > > > >
> > > > > > > > > > > > > ok so far right !!
> > > > > > > > > > > > >
> > > > > > > > > > > > > Int ser 0/0
> > > > > > > > > > > > > ip address 1.1.1.1 255.255.255.0
> > > > > > > > > > > > > frame map bla bla bla
> > > > > > > > > > > > > ip ospf prio 0
> > > > > > > > > > > > >
> > > > > > > > > > > > >
> > > > > > > > > > > > > and bingo the neighbour command disappears from
> > > > > > > > the OSPF router
> > > > > > > > > config
> > > > > > > > > > > > > ...
> > > > > > > > > > > > > Anyone know why ???
> > > > > > > > > > > > >
> > > > > > > > > > > > > Regds
> > > > > > > > > > > > > Alan E
> > > > > > > > > > > > > Brisbane, Aust
> > > > > > > > > > > > >
> > > > > > > > > > > > >
> > > > > > > > >
> > > > > > > > _______________________________________________________________________
> > > > > > > > > > > > >
> > > > > > > > > > > > > Subscription information may be found at:
> > > > > > > > > > > > > http://www.groupstudy.com/list/CCIELab.html
> > > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > >
> > > > > > > > > > > > --
> > > > > > > > > > > > Shiran Guez
> > > > > > > > > > > > MCSE CCNP NCE1
> > > > > > > > > > > > http://cciep3.blogspot.com
> > > > > > > > > > > > http://www.linkedin.com/in/cciep3
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > > > --
> > > > > > > > > > Shiran Guez
> > > > > > > > > > MCSE CCNP NCE1
> > > > > > > > > > http://cciep3.blogspot.com
> > > > > > > > > > http://www.linkedin.com/in/cciep3
> > > > > > > > > >
> > > > > > > > > >
> > > > > > > > _______________________________________________________________________
> > > > > > > > > > Subscription information may be found at:
> > > > > > > > > > http://www.groupstudy.com/list/CCIELab.html
> > > > > > > > >
> > > > > > > > > ------------------------------
> > > > > > > > > i'm is proud to present Cause Effect, a series about real
> > > > > > > > people making a
> > > > > > > >
> > > > > > > > > difference. Learn more<
> > > > > > > > http://im.live.com/Messenger/IM/MTV/?source=text_Cause_Effect
> > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > >
> > > > > > > > --
> > > > > > > > Shiran Guez
> > > > > > > > MCSE CCNP NCE1
> > > > > > > > http://cciep3.blogspot.com
> > > > > > > > http://www.linkedin.com/in/cciep3
> > > > > > > >
> > > > > > > >
> > > > > > > > _______________________________________________________________________
> > > > > > > > Subscription information may be found at:
> > > > > > > > http://www.groupstudy.com/list/CCIELab.html
> > > > > > > >
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > >
> > > > > >
> > > > > >
> > > > > > --
> > > > > >
> > > > > > Shiran Guez
> > > > > > MCSE CCNP NCE1
> > > > > > http://cciep3.blogspot.com
> > > > > > http://www.linkedin.com/in/cciep3
> > > > > >
> > > > >
> > > > >
> > > > >
> > > >
> > > >
> > > >
> > > >
> > > > --
> > > >
> > > > Shiran Guez
> > > > MCSE CCNP NCE1
> > > > http://cciep3.blogspot.com
> > > > http://www.linkedin.com/in/cciep3
> > > >
> > >
> > >
> > >
> >
> >
> >
> > --
> > Shiran Guez
> > MCSE CCNP NCE1
> > http://cciep3.blogspot.com
> > http://www.linkedin.com/in/cciep3
> >
>
>
-- Shiran Guez MCSE CCNP NCE1 http://cciep3.blogspot.com http://www.linkedin.com/in/cciep3
This archive was generated by hypermail 2.1.4 : Tue Jan 01 2008 - 12:04:30 ARST