From: Serhat Aslan (serhatworks@gmail.com)
Date: Wed Aug 01 2007 - 08:16:20 ART
Hi,
Summary :for BGP you can assume default-information originate is a kind of
redistribution. So a default route must be on the routing table.
* second tip : network *** mask *** -> you can accept this kind of
interpretation of BGP ; to redistribute of its local networks.
don't forget to check DOC-CD :)
http://www.cisco.com/univercd/cc/td/doc/product/software/ios124/124cr/hirp_r/rte_bgh1.htm#wp1073666
Serhat Aslan
<snap>
Usage Guidelines
The default-information originate command is used to configure a BGP routing
process to advertise a default route (network 0.0.0.0). A redistribution
statement must also be configured to complete this configuration or the
default route will not be advertised.
The configuration of the default-information originate command in BGP is
similar to the configuration of the network (BGP) command. The
default-information originate command, however, requires explicit
redistribution of the route 0.0.0.0. The network command requires only that
the route 0.0.0.0 is present in the Interior Gateway Protocol (IGP) routing
table. For this reason, the network command is preferred.
</snap>
On 8/1/07, Toh Soon, Lim <tohsoon28@gmail.com> wrote:
>
> Hi Brian,
>
> If I'm not wrong, "default-information originate" is also required when
> redistributing a default route into BGP.
>
> I have additional question: For BGP, can I use the command "network
> 0.0.0.0mask
> 0.0.0.0" to advertise the default route instead?
>
> What's the difference between the "redistribute + default-info originate"
> method and the "network 0.0.0.0" method? The former will have an origin
> code
> of incomplete (?) and the latter an origin code of IGP (i)?
>
> I guess I have to lab it up to know.
>
>
> Thank you.
>
> B.Rgds,
> Lim TS
>
>
> On 8/1/07, Jensen, Brian D. <bdjensen@eschelon.com> wrote:
> >
> > Hi Greg,
> >
> > In order for the redistributed route to be originated into the ospf
> > areas you will need the "default-information originate" command under
> > the ospf process on the router doing the redistribution. This will
> > generate a default route into ospf as long as the RIP route is valid. If
> > you wish to redistribute a route whether or not the RIP route is valid,
> > then you will need the "default-information originate always" command
> > under the ospf process.
> >
> > Thanks,
> >
> > Brian
> >
> > -----Original Message-----
> > From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
> > Gregory Gombas
> > Sent: Tuesday, July 31, 2007 8:29 PM
> > To: Group study
> > Subject: Re: Can you redistribute a default route from one protocol to
> > another?
> >
> > By the way, I tested this with EIGRP and the RIP default DOES get
> > redistributed into EIGRP.
> >
> > Must be an OSPF thing....
> >
> > On 7/31/07, Gregory Gombas <ggombas@gmail.com> wrote:
> > > Not sure if this falls under the body of common knowledge, but when
> > > redistributing from one protocol to another, will the default route
> > > get redistributed as well?
> > >
> > > In this case I am learning a default route via rip.
> > > I am redistributing rip into ospf but do not see the default route
> > > being redistributed.
> > >
> > > Rack8SW1#show ip route 0.0.0.0
> > > Routing entry for 0.0.0.0/0, supernet
> > > Known via "rip", distance 120, metric 4, candidate default path
> > > Redistributing via ospf 1, rip Last update from 163.8.57.5 on Vlan57,
> >
> > > 00:00:14 ago Routing Descriptor Blocks:
> > > * 163.8.57.5, from 163.8.57.5, 00:00:14 ago, via Vlan57
> > > Route metric is 4, traffic share count is 1
> > >
> > > Rack8SW1#
> > >
> > > Rack8SW1#show ip ospf database
> > >
> > > OSPF Router with ID (150.8.7.7) (Process ID 1)
> > >
> > > Router Link States (Area 0)
> > >
> > > Link ID ADV Router Age Seq# Checksum Link
> > count
> > > 10.3.3.3 10.3.3.3 1002 0x80000009 0x002E8F 3
> > > 10.4.4.4 10.4.4.4 94 0x80000010 0x00C933 3
> > > 150.8.7.7 150.8.7.7 89 0x8000000B 0x00B5BB 1
> > >
> > > Net Link States (Area 0)
> > >
> > > Link ID ADV Router Age Seq# Checksum
> > > 163.8.0.4 10.4.4.4 95 0x80000004 0x005FCE
> > > 163.8.0.134 10.4.4.4 986 0x80000007 0x008DB4
> > >
> > > Type-5 AS External Link States
> > >
> > > Link ID ADV Router Age Seq# Checksum Tag
> > > 150.8.7.0 150.8.7.7 91 0x80000006 0x00A3A5 0
> > > 163.8.7.0 150.8.7.7 91 0x80000006 0x00F942 0
> > > 163.8.57.0 150.8.7.7 91 0x80000006 0x00D138 0
> > > Rack8SW1#
> > >
> > > As you can see, show ip route says its learned via rip and is
> > > redistributing via ospf 1, but it does not appear in the OSPF
> > > database.
> > >
> > > If this is common knowledge, can someone please point me to the
> > > documentation that says this is not allowed?
> > >
> > > Thanks,
> > > Greg
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
This archive was generated by hypermail 2.1.4 : Sat Sep 01 2007 - 11:32:09 ART