>Must be a field in one of the BGP packet headers preventing IBGP from doing >this... Must consult Doyle... > >Peter Morgan
Look at the ORIGIN attribute. > > >-----Original Message----- >From: Mark M. Forest [mailto:[EMAIL PROTECTED]] >Sent: 28 December 2001 08:27 >To: [EMAIL PROTECTED] >Subject: RE: IBGP [9:943] > > >Mechanism is not important...split horizon would not actually be a factor >here, mostly due to how split horizon actually works. If it were split >horizon then we would actually only see the characteristic of no >readvertisement towards the neighbor the route was learned from. > >IBGP acts differantly in respect that if it is learned from ANY IBGP >neighbor it will not readvertise to ANY other IBGP neighbor...this is why >the need for full-mesh of IBGP neigbors is necessary. In addition the >route-reflection model would be mute. > >But the reality is that IBGP full mesh or reflection is necessary. One major >key factor is to insure that each BGP speaker is maintaining the same >database. If not then sub-optimal routing occurs and you can kiss the >integrity of your implementation goodbye. > >If anything else lies wasted, Junipers implementation of BGP is one of the >most sound in the industry. In fact, without it they could never compete in >the marketplace they are in. > >milo > > > > >-----Original Message----- >From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] >Sent: Thursday, December 27, 2001 10:47 PM >To: [EMAIL PROTECTED] >Subject: RE: IBGP [9:943] > > >Mark M. Forest wrote: >> >> BGP rules...IBGP will not re-advertise to IBGP peers any routes >> learned from >> another IBGP peer. This is why the IBGP mesh is a full-mesh. >> >> milo >> >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] >> Sent: Monday, December 24, 2001 11:39 PM >> To: [EMAIL PROTECTED] >> Subject: IBGP [9:943] >> >> >> if router-A and router-B are in the same AS,and router-A set up >> IBGP >> relationship with router-B, how does the router-A prevent the >> routes learned >> from router-B via IBGP from advertising back to router-B? >> >> regards >> http://www.groupstudy.com/list/juniper.html >> >> >> _________________________________________________________ >> Do You Yahoo!? >> Get your free @yahoo.com address at http://mail.yahoo.com >> >> >Hi: > >Of course, I know that the router-A do not advertise routes learned from >router-B via IBGP to IBGP peers, but I want to know what mechanism is used >to prevent it from occuring?(split horizon or as-path,but i think that it >does not base on as-path) > >regards >http://www.groupstudy.com/list/juniper.html > > >_________________________________________________________ >Do You Yahoo!? >Get your free @yahoo.com address at http://mail.yahoo.com >http://www.groupstudy.com/list/juniper.html >http://www.groupstudy.com/list/juniper.html Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=30438&t=943 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
