EIGRP understands ip default-network, in fact it's the basis of a very important function in the configuration of EIGRP: default route filtering.
'ip default-network' is a classful command. If you use it with prefixes longer than a classful boundary, you must have the prefix as well as the classful boundary of the prefix known in the topology table of the routing protocol in question. You must then also configure the class boundary with the 'ip default-network' along with the more specific prefix you really mean to advertise as the default network. Just because a route is in the routing table, doesn't mean its in the routing protocol topology table. This is why a static to 0.0.0.0 must be redistributed into EIGRP in someway, in order to use 'ip default-network 0.0.0.0'. To EIGRP, a route to 0.0.0.0 looks like any other class A network. Which brings me to another point... Do you really want a default network to 0.0.0.0 floating around your EIGRP domain. The default-network command is an enhancement to default routing allowing you to flag any network, not just 0.0.0.0 as a default. Reconsider your network topology and take a look at http://www.cisco.com/warp/public/105/default.html You could have just put ip default-network 'network of serial interface' and a default route would have went all through your EIGRP routing domain. (Except routers configured to filter the route from being a default. See 'default-information in/out/allowed' under the 'router eigrp ') WAYNE BAETY, MCSE, A1C, USAF Network Systems Trainer > -----Original Message----- > From: Cisco Nuts [mailto:[EMAIL PROTECTED]] > Sent: Friday, January 11, 2002 10:39 AM > To: [EMAIL PROTECTED] > Subject: RE: Fefault route for eigrp? [7:31592] > > You are absolutely right, my friend. I bumped into this tech-note from cco > and it says the same..I tried it and found out that this is the only way > for > EIGRP to work!! Very strange!! I have BGP running on the router along with > EIGRP and also a default route of 0.0.0.0 pointing to my outbound serial. > Then after redistributing this static under eigrp, all other routers > inside > my network can get to outside networks learned via BGP..I wonder why IGRP > understands the ip default route but not EIGRP...Anyone has any ideas on > this?? > Thank you for your help. :-) > > >From: "s vermill" > >Reply-To: "s vermill" > >To: [EMAIL PROTECTED] > >Subject: RE: Fefault route for eigrp? [7:31592] > >Date: Thu, 10 Jan 2002 19:37:07 -0500 > > > >EIGRP behaves a little differently than all of the other protocols. You > >first have to define a static 'ip route 0.0.0.0 0.0.0.0 x.x.x.x' and then > >add a 'network 0.0.0.0' to your EIGRP config. I think you have to > >'redistribute static' as well. It will not propogate a default as a > result > >of the 'default-network' command. > > > >Regards > _________________________________________________________________ > Chat with friends online, try MSN Messenger: http://messenger.msn.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=31622&t=31592 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
