Actually, it's a little different than that... The bottom line (with every routing protocol) is that the RIB (protocol itself) makes a decision BEFORE handing it to the routing table. Since AD happens at the routing table, the AD is never actually part of the equation.
>From the long list of BGP Path Selection rules, internal routes will be chosen over external routes. The AD part comes after this choice. Very much like how an external OSPF route (AD 110) may be chosen over an "internal" RIP route (AD 120) it all has to do with the order of the selection process and THEN the difference of AD. HTH, Scott Morris, CCIE4 (R&S/ISP-Dial/Security/Service Provider) #4713, JNCIE-M #153, JNCIS-ER, CISSP, et al. CCSI/JNCI-M/JNCI-ER VP - Technical Training - IPexpert, Inc. IPexpert Sr. Technical Instructor [EMAIL PROTECTED] Telephone: +1.810.326.1444 Fax: +1.810.454.0130 http://www.ipexpert.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Suresh Mishra Sent: Thursday, April 03, 2008 8:34 AM To: Michael Berger Cc: [email protected] Subject: Re: [OSL | CCIE_RS] EBGP or IBGP BGP is the only routing protocol where decision is made based on the path attributes than Administrative distance which comes after Weight, Local Pref, AS path, origin and Med in that order and AD is the second last tie breaker in considering the best route. Thanks Suresh On Thu, Apr 3, 2008 at 5:50 AM, Michael Berger <[EMAIL PROTECTED]> wrote: > Hi Ajay, > > my understanding is that local pref comes much higher than eBGP vs > iBGP in the decision process. So iBGP with higher local pref will be > installed in BGP table. > > Regards, > Michael > > > Ajay Chenampara wrote: > > > > > Which is preferred: an eBGP learned route or an iBGP learnt route > > with > higher value of local preference attribute? > > > > My understanding was that eBGP with the lower AD will always be chosen. > But Jeff Doyle's Vol 2 routing policies section seems to indicate > otherwise...... > > > > -------------------------------------------------------------------- > > ---- You rock. That's why Blockbuster's offering you one month of > > Blockbuster > Total Access > <http://us.rd.yahoo.com/evt=47523/*http://tc.deals.yahoo.com/tc/blockb > uster/text5.com>, > No Cost. > > >
