Ho Scott, I tried the same thing using ttl-security. I was able to get the neighbor relationship up but could not get the routes exchanged as next-hop was showing unreachable.
Suresh On 6/10/08, Scott Morris <[EMAIL PROTECTED]> wrote: > > Two should work just fine. Does for me anyway. > > First, I pasted in the configs from Cat1, R1 and R2 as is. Then waited for > spanning tree. ;) > > R2(config-if)#do ping 200.0.0.1 > > Type escape sequence to abort. > Sending 5, 100-byte ICMP Echos to 200.0.0.1, timeout is 2 seconds: > ..... > Success rate is 0 percent (0/5) > R2(config-if)# > *Jun 11 04:01:20.395: %BGP-5-ADJCHANGE: neighbor 200.0.0.1 Up > R2(config-if)#do ping 200.0.0.1 > > Type escape sequence to abort. > Sending 5, 100-byte ICMP Echos to 200.0.0.1, timeout is 2 seconds: > !!!!! > Success rate is 100 percent (5/5), round-trip min/avg/max = 4/5/8 ms > R2(config-if)#do sh run | s bgp > router bgp 65256 > no synchronization > bgp log-neighbor-changes > bgp confederation identifier 200 > bgp confederation peers 65078 > neighbor 150.50.24.4 remote-as 300 > neighbor 150.50.24.4 filter-list 1 out > neighbor 150.50.100.5 remote-as 65256 > neighbor 150.50.100.5 next-hop-self > neighbor 150.50.100.5 route-map 200Filter out > neighbor 200.0.0.1 remote-as 100 > neighbor 200.0.0.1 ebgp-multihop 3 > no auto-summary > <<<Notice here that the multihop is 3 as the solutions have, and see above > where the peer came up>>> > > R2(config-if)#router bgp 65256 > R2(config-router)#no neigh 200.0.0.1 > R2(config-router)# > *Jun 11 04:02:01.099: %BGP-5-ADJCHANGE: neighbor 200.0.0.1 Down Neighbor > deleted > R2(config-router)#do sh run | s bgp > router bgp 65256 > no synchronization > bgp log-neighbor-changes > bgp confederation identifier 200 > bgp confederation peers 65078 > neighbor 150.50.24.4 remote-as 300 > neighbor 150.50.24.4 filter-list 1 out > neighbor 150.50.100.5 remote-as 65256 > neighbor 150.50.100.5 next-hop-self > neighbor 150.50.100.5 route-map 200Filter out > no auto-summary > R2(config-router)#neigh 200.0.0.1 remote-as 100 > R2(config-router)#do sh run | s bgp > router bgp 65256 > no synchronization > bgp log-neighbor-changes > bgp confederation identifier 200 > bgp confederation peers 65078 > neighbor 150.50.24.4 remote-as 300 > neighbor 150.50.24.4 filter-list 1 out > neighbor 150.50.100.5 remote-as 65256 > neighbor 150.50.100.5 next-hop-self > neighbor 150.50.100.5 route-map 200Filter out > neighbor 200.0.0.1 remote-as 100 > no auto-summary > R2(config-router)#neigh 200.0.0.1 ebgp-multihop 2 > <<<Note the removal of the peer, and the appropriate deletion. Then it's > recreated with multihop 2>>> > > > R2(config-router)#do sh ip bgp sum > BGP router identifier 200.0.0.2, local AS number 65256 > BGP table version is 5, main routing table version 5 > > Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down > State/PfxRcd > 150.50.24.4 4 300 0 0 0 0 0 never Active > 150.50.100.5 4 65256 0 0 0 0 0 never Active > 200.0.0.1 4 100 0 0 0 0 0 never Active > <<<Ready and waiting>>> > > R2(config-router)#do deb ip pack det > IP packet debugging is on (detailed) > R2(config-router)# > *Jun 11 04:03:01.007: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), routed via FIB > *Jun 11 04:03:01.007: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 44, sending > *Jun 11 04:03:01.011: TCP src=34362, dst=179, seq=1444273798, ack=0, > win=16384 SYN > *Jun 11 04:03:01.015: IP: tableid=0, s=200.0.0.1 (FastEthernet1/0), d= > 150.50.17.2 (FastEthernet1/0), routed via RIB > *Jun 11 04:03:01.015: IP: s=200.0.0.1 (FastEthernet1/0), > d=150.50.17.2(FastEthernet1/0), len 44, rcvd 3 > *Jun 11 04:03:01.015: TCP src=179, dst=34362, seq=2326681210, > ack=1444273799, win=16384 ACK SYN > *Jun 11 04:03:01.015: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), routed via FIB > *Jun 11 04:03:01.015: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 40, sending > *Jun 11 04:03:01.015: TCP src=34362, dst=179, seq=1444273799, > ack=2326681211, win=16384 ACK > *Jun 11 04:03:01.023: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEth > R2(config-routeernet1/0), routed via FIB > *Jun 11 04:03:01.023: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 85, sending > *Jun 11 04:03:01.023: TCP src=34362, dst=179, seq=1444273799, > ack=2326681211, win=16384 ACK PSH > *Jun 11 04:03:01.043: IP: s=200.0.0.1 (FastEthernet1/0), d=150.50.17.2, > len 104, rcvd 0 > *Jun 11 04:03:01.047: TCP src=179, dst=34362, seq=2326681211, > ack=1444273844, win=16339 ACK PSH > *Jun 11 04:03:01.051: %BGP-5-ADJCHANGE: neighbor 200.0.0.1 Up > *Jun 11 04:03:01.051: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), routed via FIB > *Jun 11 04:03:01.051: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 59, sending > *Jun 11 04:03:01.051: TCP src=34362, dst=179, seq=1444273844, > ack=2326681275, win=16320 ACK PSH > *Jun 11 04:03:01.059: IP: s=200.0.0.1 (FastEthernet1/0), d=150.50.17.2, > len 108, rcvd 0 > *Jun 11 04:03:01.059: TCP src=179, dst=34362, seq=2326681275, > ack=1444273863, win=16320 ACK PSH > *Jun 11 04:03:01.059: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), routed via FIB > *Jun 11 04:03:01.059: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 78, sending > *Jun 11 04:03:01.059: TCP src=34362, dst=179, seq=1444273863, > ack=2326681343, win=16252 ACK PSH > *Jun 11 04:03:01.071: IP: s=200.0.0.1 (FastEthernet1/0), d=150.50.17.2, > len 78, rcvd 0 > *Jun 11 04:03:01.071: TCP src=179, dst=34362, seq=2326681343, > ack=1444273901, win=16282 ACK PSH > *Jun 11 04:03:01.275: IP: tableid=0, s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), routed via FIB > *Jun 11 04:03:01.275: IP: s=150.50.17.2 (local), > d=200.0.0.1(FastEthernet1/0), len 40, sending > *Jun 11 04:03:01.275: TCP src=34362, dst=179, seq=1444273901, > ack=2326681381, win=16214 ACKr)# > R2(config-router)#do sh ip bgp sum > BGP router identifier 200.0.0.2, local AS number 65256 > BGP table version is 7, main routing table version 7 > 2 network entries using 234 bytes of memory > 2 path entries using 104 bytes of memory > 2/1 BGP path/bestpath attribute entries using 248 bytes of memory > 1 BGP AS-PATH entries using 24 bytes of memory > 0 BGP route-map cache entries using 0 bytes of memory > 0 BGP filter-list cache entries using 0 bytes of memory > BGP using 610 total bytes of memory > BGP activity 4/2 prefixes, 4/2 paths, scan interval 60 secs > > Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down > State/PfxRcd > 150.50.24.4 4 300 0 0 0 0 0 never Active > 150.50.100.5 4 65256 0 0 0 0 0 never Active > 200.0.0.1 4 100 5 4 7 0 0 00:00:10 > 2 > R2(config-router)#do un all > All possible debugging has been turned off > R2(config-router)# > > So we see the packets coming in sourced from 150.50.17.2 destined for the > loopback interface. Multihop config is 2 and it works! > > If we were going to/from the loopback on R1, then that would add another > hop. But from one loopback to the other loopback may require that you have > another hop in there. :) > > HTH, > > Scott > > ------------------------------ > *From:* Carlos Valero [mailto:[EMAIL PROTECTED] > *Sent:* Tuesday, June 10, 2008 11:02 PM > *To:* 'OSL CCIE Routing and Switching Lab Exam'; [EMAIL PROTECTED] > *Subject:* Re: [OSL | CCIE_RS] EBGP Multihop > > > Hi, > > I had forgotten to ask you a question about ebgp-multihop. > Since this issue was raised, this question came back to my mind. > > This is about BGP Lab 7 (v9.0). I know you don't have v9.0 anymore, but > this should not be too complicated for you. > > One of the initial tasks was to configure R1 on AS 100 and R2 on AS 200, > but peering with R1's loopback. > > Of course we need to use ebgp-multihop in this case. But while I was > expecting to see "ebgp-multihop 2", the actual solution used "ebgp-multihop > 3" > > I tried "ebgp-multihop 2" just to see, but of course it did not work! > > But I'm not sure why. > > If they were peering using a Serial Link, then "ebgp-multihop 2" would be > OK; I know that. > But in this case R1 and R2 are connected through Switch 1 on VLAN 12. > > Does the Switch count as an additional hop? > > If that's the case, is it because the Switch is acting as Layer 3 device? > > What if the switch was a pure Layer 2 device, with no VLAN? > > Would I still need "ebgp-multihop 3" instead of "ebgp-multihop 2" ? > > > > > > --- On *Tue, 6/10/08, Scott Morris <[EMAIL PROTECTED]>* wrote: > > From: Scott Morris <[EMAIL PROTECTED]> > Subject: Re: [OSL | CCIE_RS] EBGP Multihop > To: "'OSL CCIE Routing and Switching Lab Exam'" < > [email protected]> > Date: Tuesday, June 10, 2008, 3:32 PM > > It's mandatory to have reachability. :) However you choose to do that > in order to build your session is between you and your lab requirements! > > But no reachability = no bgp session! > > HTH, > > Scott > > ------------------------------ > *From:* [EMAIL PROTECTED] [mailto: > [EMAIL PROTECTED] *On Behalf Of *Hari > *Sent:* Tuesday, June 10, 2008 3:01 PM > *To:* [email protected] > *Subject:* [OSL | CCIE_RS] EBGP Multihop > > > Hi all, > > While configuring EBGP Multihop command in BGP , do we need to configure > IGP route or static route for that particular neighbor? > > Is it mandatory to configure IGP route or static route ? > > Thanks > Hari > > ------------------------------ > Bring your gang together. Do your thing. Find your favourite Yahoo! > Group.<http://in.rd.yahoo.com/tagline_groups_9/*http://in.promos.yahoo.com/groups/> > > >
