That will configure IPv4 unicast peering with 4.4.4.4 using a peer-group. That won't help you *much* with multicast RPF.
-- Marko Milivojevic - CCIE #18427 (SP R&S) Senior CCIE Instructor / Managing Partner - IPexpert On Sun, Jan 27, 2013 at 4:12 PM, Sheraz Sheraz <[email protected]> wrote: > Hey Marko i found this if you think that MBGP can help to figure this task. > I'm sharing Just for the sake of learning from you! can we use following way > as well from exam point of view? > > > >> > > > >> > router bgp 34 >>>>>>>>>> neighbor mygroup peer-group nlri unicast multicast > >> > > > >> > bgp log-neighbor-changes >> > > > >> > neighbor 4.4.4.4 remote-as 34 > >>>>>>>>>>> neighbor 4.4.4.4 peer-group mygroup >> > > > >> > neighbor 4.4.4.4 update-source Loopback0 > >> > > > >> > neighbor 4.4.4.4 activate >> > > > >> > neighbor 4.4.4.4 default-originate >> > > > >> > no auto-summary > > > >> > From: [email protected] >> > To: [email protected] >> > Date: Sun, 27 Jan 2013 00:33:19 +0500 >> > CC: [email protected] >> > Subject: Re: [OSL | CCIE_RS] neighbor default-originate >> > >> > Is it CCIE R&S or SP? >> > >> > If its R&S please include me as well & can you please share some >> > material for lab preparation of CCIE R&S i have to prepare my lab. >> > >> > Regards >> > Sheraz >> > >> > > From:[email protected] >> > > To: [email protected] >> > > Date: Sun, 27 Jan 2013 00:01:47 +0500 >> > > CC: [email protected] >> > > Subject: Re: [OSL | CCIE_RS] neighbor default-originate >> > > >> > > Dear Markoz, >> > > >> > > Then things have to deal according to the tasks of CCIE Exam... in >> > > this case you are right, one must have to perform the task like that if >> > > this >> > > is the case. >> > > >> > > Regards >> > > Sheraz >> > > >> > > > From: [email protected] >> > > > Date: Sat, 26 Jan 2013 10:19:22 -0800 >> > > > Subject: Re: [OSL | CCIE_RS] neighbor default-originate >> > > > To: [email protected] >> > > > CC: [email protected]; [email protected] >> > > > >> > > > Sheraz, >> > > > >> > > > I'm pretty sure Lukasz knew why he had an RPF failure. This is to be >> > > > expected in the lab and you need to be able to handle it >> > > > appropriately. Enabling PIM on all the interfaces may not be an >> > > > option >> > > > (lab restrictions) and knowing how to recover from the RPF failure >> > > > is >> > > > an essential skill for the multicast in the lab. >> > > > >> > > > Lukasz was trying to replicate this scenario: >> > > > >> > > > http://blog.ipexpert.com/2010/12/29/multicast-rpf-failure-recovery-using-bgp/ >> > > > >> > > > -- >> > > > Marko Milivojevic - CCIE #18427 (SP R&S) >> > > > Senior CCIE Instructor / Managing Partner - IPexpert >> > > > >> > > > On Sat, Jan 26, 2013 at 9:24 AM, Sheraz Sheraz <[email protected]> >> > > > wrote: >> > > > > Please read the below facts it will help you to understand that >> > > > > why RPF is being failed after disabling PIM on some interfaces. >> > > > > >> > > > > >> > > > > "When a multicast packet enters a router's interface, it will >> > > > > lookup the >> > > > > list of networks that are reachable via that input interface i.e., >> > > > > it >> > > > > checks the reverse path of the packet. If the router finds a >> > > > > matching >> > > > > routing entry for the source IP of the multicast packet, the RPF >> > > > > check >> > > > > passes and the packet is forwarded to all other interfaces that >> > > > > are >> > > > > participating in multicast for this multicast group. If the RPF >> > > > > check >> > > > > fails the packet will be dropped. As a result the forwarding of >> > > > > the >> > > > > packet is decided based upon the reverse path of the packet rather >> > > > > than >> > > > > the forward path. RPF routers only forward packets that come into >> > > > > the >> > > > > interface that also hold the routing entry for the source of the >> > > > > packet, >> > > > > thus breaking any loop" >> > > > > >> > > > > >> > > > > >> > > > >> From: [email protected] >> > > > >> To: [email protected]; [email protected] >> > > > >> Date: Sat, 26 Jan 2013 22:10:10 +0500 >> > > > >> Subject: Re: [OSL | CCIE_RS] neighbor default-originate >> > > > >> >> > > > >> Hi, >> > > > >> >> > > > >> I think BGP can help to work as base line for multicast traffic >> > > > >> but hence you need PIM as well. Although BGP it self needs baseline >> > > > >> static >> > > > >> or IGP protocols to work properly! You migh have have to enable PIM >> > > > >> for >> > > > >> multicast traffic to work through out the routing hops and and any >> > > > >> IGP! in >> > > > >> my case i have enabled PIM with RP on my routers & Multi layer >> > > > >> switches as >> > > > >> well & have never seen RPF or RP failure! multicast works >> > > > >> properly.EGP & IGP >> > > > >> protocols are not the suitable choice since "protocol independent >> > > > >> Multicast" >> > > > >> PIM has been designed for multicast traffic.Look both BGP & IGP >> > > > >> protocols >> > > > >> takes decision on the base of destination address while multicast >> > > > >> needs >> > > > >> source base decisions! the nature and working nature of both dynamic >> > > > >> protocols & multicast are different. >> > > > >> >> > > > >> >> > > > >> "Multicast RPF, typically denoted simply as RPF, is used in >> > > > >> conjunction with a multicast routing protocols such as MSDP and >> > > > >> PIM-SM >> > > > >> to ensure loop-free forwarding of multicast packets. In multicast >> > > > >> routing the decision to forward traffic is based upon source >> > > > >> address and >> > > > >> not on destination address as is the case with unicast routing. >> > > > >> It does >> > > > >> this by utilizing either a dedicated multicast routing table or >> > > > >> alternatively the router's native unicast routing table" >> > > > >> >> > > > >> >> > > > >> Regards >> > > > >> Sheraz >> > > > >> >> > > > >> > Date: Sat, 26 Jan 2013 00:55:13 +0000 >> > > > >> > From: [email protected] >> > > > >> > To: [email protected] >> > > > >> > Subject: [OSL | CCIE_RS] neighbor default-originate >> > > > >> > >> > > > >> > Hi All, >> > > > >> > >> > > > >> > >> > > > >> > I am just trying to replicate Marko scenario from blog >> > > > >> > Multicast RPF >> > > > >> > Failure: Recovery Using BGP. I have only changed addressing but >> > > > >> > other >> > > > >> > details are the same. I have ipv4 unicast working and Pim >> > > > >> > enabled. >> > > > >> > I have disabled pim between R3 and R4 on Fa interface and I can >> > > > >> > see RPF >> > > > >> > failure. I set up MP-BGP and that is active as well >> > > > >> > but..command >> > > > >> > neighbor x.x.x.x default-originate does not seem to send >> > > > >> > default route >> > > > >> > to the neighbor. >> > > > >> > >> > > > >> > >> > > > >> > R3 >> > > > >> > >> > > > >> > router bgp 34 >> > > > >> > no bgp default ipv4-unicast >> > > > >> > bgp log-neighbor-changes >> > > > >> > neighbor 4.4.4.4 remote-as 34 >> > > > >> > neighbor 4.4.4.4 update-source Loopback0 >> > > > >> > ! >> > > > >> > address-family ipv4 multicast >> > > > >> > neighbor 4.4.4.4 activate >> > > > >> > neighbor 4.4.4.4 default-originate >> > > > >> > no auto-summary >> > > > >> > >> > > > >> > >> > > > >> > R3#show bgp ipv4 multicast neighbors 4.4.4.4 | b def >> > > > >> > Default information originate, default not sent >> > > > >> > >> > > > >> > >> > > > >> > R4 >> > > > >> > >> > > > >> > >> > > > >> > router bgp 34 >> > > > >> > no bgp default ipv4-unicast >> > > > >> > bgp log-neighbor-changes >> > > > >> > neighbor 3.3.3.3 remote-as 34 >> > > > >> > neighbor 3.3.3.3 update-source Loopback0 >> > > > >> > ! >> > > > >> > address-family ipv4 multicast >> > > > >> > neighbor 3.3.3.3 activate >> > > > >> > no auto-summary >> > > > >> > no synchronization >> > > > >> > exit-address-family >> > > > >> > R4# >> > > > >> > R4#show bgp ipv4 mul >> > > > >> > >> > > > >> > >> > > > >> > R4#show bgp ipv4 mul s >> > > > >> > Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down >> > > > >> > State/PfxRcd >> > > > >> > 3.3.3.3 4 34 61 59 3 0 0 00:34:57 >> > > > >> > 0 >> > > > >> > >> > > > >> > >> > > > >> > I guess I misinterpret something. Where is the problem? >> > > > >> > >> > > > >> > >> > > > >> > THanks, >> > > > >> > >> > > > >> > >> > > > >> > _______________________________________________ >> > > > >> > For more information regarding industry leading CCIE Lab >> > > > >> > training, please visit www.ipexpert.com >> > > > >> > >> > > > >> > Are you a CCNP or CCIE and looking for a job? Check out >> > > > >> > www.PlatinumPlacement.com >> > > > >> > >> > > > >> > http://onlinestudylist.com/mailman/listinfo/ccie_rs >> > > > >> >> > > > >> _______________________________________________ >> > > > >> For more information regarding industry leading CCIE Lab >> > > > >> training, please visit www.ipexpert.com >> > > > >> >> > > > >> Are you a CCNP or CCIE and looking for a job? Check out >> > > > >> www.PlatinumPlacement.com >> > > > >> >> > > > >> http://onlinestudylist.com/mailman/listinfo/ccie_rs >> > > > > >> > > > > _______________________________________________ >> > > > > For more information regarding industry leading CCIE Lab training, >> > > > > please visit www.ipexpert.com >> > > > > >> > > > > Are you a CCNP or CCIE and looking for a job? Check out >> > > > > www.PlatinumPlacement.com >> > > > > >> > > > > http://onlinestudylist.com/mailman/listinfo/ccie_rs >> > > >> > > _______________________________________________ >> > > For more information regarding industry leading CCIE Lab training, >> > > please visit www.ipexpert.com >> > > >> > > Are you a CCNP or CCIE and looking for a job? Check out >> > > www.PlatinumPlacement.com >> > > >> > > http://onlinestudylist.com/mailman/listinfo/ccie_rs >> > >> > _______________________________________________ >> > For more information regarding industry leading CCIE Lab training, >> > please visit www.ipexpert.com >> > >> > Are you a CCNP or CCIE and looking for a job? Check out >> > www.PlatinumPlacement.com >> > >> > http://onlinestudylist.com/mailman/listinfo/ccie_rs >> >> _______________________________________________ >> For more information regarding industry leading CCIE Lab training, please >> visit www.ipexpert.com >> >> Are you a CCNP or CCIE and looking for a job? Check out >> www.PlatinumPlacement.com >> >> http://onlinestudylist.com/mailman/listinfo/ccie_rs _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com http://onlinestudylist.com/mailman/listinfo/ccie_rs
