From: fwells12 (fwells12@xxxxxxxxxxx)
Date: Sun Jan 28 2001 - 19:37:49 GMT-3
You need to use a network that is not one of the networks in your network
statements. The network you choose however needs to have a route in your
route table. You would not need default route to route only within your own
domain. The default route is therefore used to get to networks which are
outside your own domain.
Here's a excerpt I just read on CCO that might help:
http://www.cisco.com/univercd/cc/td/doc/product/software/ssr83/rpc_r/53992.h
tm#xtocid2008054
Picking a Default Route
When default information is being passed along through the dynamic routing
protocol, no further configuration is required. The system will periodically
scan its routing table to choose the optimal default network as its default
route. In the case of RIP and HELLO, there will be only one choice, network
0.0.0.0. In the case of IGRP, there may be several networks that can be
candidates for the system default. The router uses both administrative
distance and metric information to determine the default route. The selected
default route appears in the gateway of last resort display of the EXEC
command show ip route.
If dynamic default information is not being passed to the router, candidates
for the default route may be specified with the ip default-network
subcommand. In this usage, ip default-network takes a nonconnected network
as an argument. If this network appears in the routing table from any source
(dynamic or static), then it is flagged as a candidate default route and is
subject to being chosen as the default route for the router. Multiple ip
default-network commands may be given. All candidate default routes, both
static (that is, flagged by ip default-network) and dynamic, appear in the
routing table preceded by an asterisk.
Example:
In the following example, a static route to network 10.0.0.0 is defined as
the static default route.
ip route 10.0.0.0 131.108.3.4
ip default-network 10.0.0.0
If the following global configuration command was issued on a router not
connected to network 129.140.0.0, then the router might choose the path to
that network as a default route when the network appeared in the routing
table.
ip default-network 129.140.0.0
----- Original Message -----
From: D. J. Jones <meganac@home.com>
To: Jeremy Gray <jeremy.gray@virgin.net>; <ccielab@groupstudy.com>
Sent: Sunday, January 28, 2001 1:42 PM
Subject: Re: Igrp / ospf and redistribution - revisted
> I think I understand what you are saying about the ip default-network
> command, but I'm unclear how it applies here since the only connected
> network in the igrp domain is 171.68.62.93/26? To me that would imply the
> following:
>
> router igrp 1
> network 171.68.0.0
> !
> ip classless
> ip default-network 171.68.0.0
>
> This I don't think can work because if router r4 in this example has other
> interfaces using addresses from net 171.68.0.0, how would you determine
> which interface is the default to network 0.0.0.0?
>
> Thanks..dj
>
>
>
> ----- Original Message -----
> From: "Jeremy Gray" <jeremy.gray@virgin.net>
> To: <ccielab@groupstudy.com>
> Sent: Sunday, January 28, 2001 1:08 PM
> Subject: RE: Igrp / ospf and redistribution - revisted
>
>
> >
> >
> > IGRP can be painful if you're used to more complex and forgiving
> protocols.
> >
> > In this instance it needs feeding with a default network. IGRP will
> > otherwise perform only strict classful lookups.
> >
> > ip default-network n.n.0.0
> >
> > Caslow recommends this route be a classful subnet 172.16.0.0 for
example.
> > THe route is then tagged in show ip route as a 'candidate default route'
> > using an *.
> >
> > Your IGRP routers should then follow this network as though it where
> 0.0.0.0
> >
> > Jeremy.
> > -----Original Message-----
> > From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
> > D. J. Jones
> > Sent: 28 January 2001 17:57
> > To: Nigel Taylor; Connary, Julie Ann
> > Cc: ccielab@groupstudy.com
> > Subject: Re: Igrp / ospf and redistribution - revisted
> >
> >
> > Are you using the redistribute subnets under the ospf process for igrp?
> >
> > ----- Original Message -----
> > From: "Nigel Taylor" <nigel_taylor@hotmail.com>
> > To: "Connary, Julie Ann" <jconnary@cisco.com>
> > Cc: <ccielab@groupstudy.com>
> > Sent: Wednesday, January 24, 2001 7:48 AM
> > Subject: Igrp / ospf and redistribution - revisted
> >
> >
> > > Julie Ann,
> > > Here's the original mesage/layout of the scanerio I
> posted
> > > to
> > > the group. The lab also specified to only redistribute the OSPF
domain
> > > routes into the IGRP domain. I do have "red ospf xx metric x x x
x
> > x"
> > > under the IGRP process. Now I do get a 172.16.0.0/16 into the IGRP
> > > domain but I cannont ping all interfaces from the IGRP
> > > domain(another requirement).
> > >
> > > Now the lab also specifies "NO Statics". I'm also working on a
> > > OSPF - EIGRP - IGRP redistribution lab. In my case the lab required
> > > you to only use 172.17.59.x for the EIGRP and OSPF domains.
> > > The requirement called for the IGRP domain that is connected to
> > > use 171.68.62.93 w/ a 26 bit mask. Let's try some ASCII art.....
> > >
> > >
> > > EIGRP(E1)------R3 -------(S1)---(FR, Area 0)---R2 -----R1-(Area 1)
> > > / \
> > > / \
> > > IGRP OSPF(Area 2)
> > > (E0) (E2)
> > > / \
> > > R4 R5
> > > \
> > > (Area 3)
> > >
> > >
> > > Ok, I've got the EIGRP(E1) using 172.17.59.0/29. The OSPF domain is
> > > using 172.17.59.48/28(S1) and (E2) using 172.17.59.68/30. As I said
the
> > > IGRP(E0) is assigned 171.68.62.93 w a /26 on R3's E0 interface. I've
> > > read through the list thread on this but I'm still unable to see a
> route
> > > to the OSPF from the IGRP domain. I'm so tired at this point can
> > > anyone shed some light on this for me...
> > >
> > > TIA
> > >
> > > Nigel...
> > >
> > >
> > >
> > >
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:27:46 GMT-3