From: Bhaskar Sivanesan (bas_bharath@yahoo.com)
Date: Mon Aug 06 2007 - 05:28:02 ART
another solution I could think of is, run a GRE tunnel between R1 and BB1 and
use this prefix for matching in the route-map.
cheers
----- Original
Message ----
From: Ben <bmunyao@gmail.com>
To: Donghai Zhang
<zdh1207@gmail.com>
Cc: Prasad Shemrudkar (pshemrud) <pshemrud@cisco.com>;
Cisco certification <ccielab@groupstudy.com>
Sent: Sunday, August 5, 2007
7:14:00 AM
Subject: Re: OSPF default route
Hi Prasad,
I think Brian's
solution is brilliant, and doesn't introduced any IGP
breaking the
requirements of the lab, unless they do not allow the use of a
static route
for the task. In a nutshell, introduce a tracked static route
that's more
specific than the /24 subnet of the interface to the backbone
router, and use
that in your route-map.
Ben
On 8/5/07, Donghai Zhang <zdh1207@gmail.com>
wrote:
>
> Dear Prasad,
> Yeath, routing protocol here maybe no permitted in
the lab exam,but it's
> the
> only way I found to solve this problem.Let me
if you see any one
> better.thanks.
>
>
> 2007/8/5, Prasad Shemrudkar
(pshemrud) <pshemrud@cisco.com>:
> >
> > Hi Donghai,
> >
> >
> >
> > I too
think this will work, but from exam point of view, not sure how
> good
> > it
is to use a dynamic routing protocol when not asked to!!
> >
> >
> >
> > Just
wanted to check if my logic was right and everyone was with me on
> > this
one.
> >
> >
> >
> > Prasad
> >
> >
> > ------------------------------
> >
>
> *From:* Donghai Zhang [mailto:zdh1207@gmail.com]
> > *Sent:* Saturday,
August 04, 2007 7:12 PM
> > *To:* Prasad Shemrudkar (pshemrud)
> > *Cc:* Cisco
certification
> > *Subject:* Re: OSPF default route
> >
> >
> >
> > Dear
Prasad,
> >
> > I think you're right. the C route is indeed there even when
BB1 is
> > disconncted.I think you could try another way. Since you need to
make
> sure
> > BB1 is ACTIVE otherwise you would not advertise the default
route. So
> you
> > have to let R1 know if BB1 is alive. There is a way to
solve this. Make
> a
> > Rip between R1 and BB1, from which R1 should learn a
route(say,a
> Loopback
> > address)from BB1.If the learned route
disappear,then R1 knows it lose
> the
> > connection to BB1.Here is the
configuration:
> >
> > R1
> >
> > router rip
> >
> > version 2
> >
> > no auto
> >
> > network 204.12.0.0
> >
> >
> >
> > route-map RIP
> >
> > match ip
address 1
> >
> > access-list 1 permit 3.0.0.0
> >
> >
> >
> > router os 1
> >
> > default-information originate route-map RIP
> >
> >
> >
> > BB1
> >
> >
int loopback 1
> >
> > ip add 3.3.3.3 255.255.255.0
> >
> > router rip
> >
> >
version 2
> >
> > no auto
> >
> > network 3.0.0.0
> >
> > network 204.12.0.0
>
>
> > ------------------------------------------------------
> >
> > Now you
got what you want.
> >
> >
> >
> >
> >
> > 2007/8/4, Prasad Shemrudkar
(pshemrud) <pshemrud@cisco.com>:
> >
> > Hi,
> >
> > I have a situation
wherein there are 2 routers say R1 and BB1 connected
> > to a switch. The
subnet is 204.12.1.0/24. R1 needs to conditionally
> > advertise a default
route in ospf domain if it is CONNECTED to BB1. Now
> > I have used the
following configuration on R1 but do not think its
> > correct (for the reason
explained below the configuration).
> >
> > router ospf 1
> > router-id
150.1.3.3
> > log-adjacency-changes
> > area 0 authentication message-digest
>
> area 23 virtual-link 150.1.2.2
> > area 34 authentication
> > area 34
virtual-link 150.1.4.4
> > redistribute connected subnets route-map CONNECTED
> > redistribute rip subnets route-map RIP-->OSPF
> > network 191.1.13.3
0.0.0.0 area 13
> > network 191.1.23.3 0.0.0.0 area 23
> > network 191.1.34.3
0.0.0.0 area 34
> > default-information originate route-map DEFAULT
> > !
> >
route-map DEFAULT permit 10
> > match ip address prefix-list BB1
> > !
> > ip
prefix-list BB1 seq 10 permit 204.12.1.0/24
> >
> > My point is, that since
both router connect on Ethernet (via switch),
> > even if BB1 looses
connectivity to the switch, the directly connected
> > route "C
204.12.1.0/24 is directly connected, Ethernet1/0" will
> still
> > be shown in
R1's routing table (as that one is still connected) and
> > hence R1 will
continue advertising the default route in OSPF even though
> > there is no
connectivity between R1 and BB1.
> >
> > I dunno but got a feeling, have a
wrong logic as the solution has
> > configured it the same way too!!
> >
> >
Thanks in Advance,
> >
> > Prasad
> >
> >
This archive was generated by hypermail 2.1.4 : Sat Sep 01 2007 - 11:32:09 ART