Re: pinging across an MPLS cloud (PE-PE) not working

Jules:

 The problem isn't explicitly the network type but the fact that the
prefix won't match any routes. Another way to overcome this would be
to advertise area 4 range 4.4.4.4 255.0.0.0 in the OSPF routing
process of R4 without changing the network type of the lo0 one R4. A
good practice is to add network typ point to point on any loopbacks
being advertised into OSPF unless the exam restricts this. Then the
area range could be used.

I saw enough from the show commands you provided to understand both
the topology and the 4.4.4.4 being advertised as a host route. These
were great show commands to ID your problem. Yes this stuff will come
through experience and now you know. This is a common issue with OSPF.
I have learned and re learned this one many times and now can catch
it. Always try to make sure that the network advertised is the network
on the device. In this case it was not.

One other tip is to hard code router-id and make sure it matches BGP
router ID. This is also a gotcha of OSPF and is now an RFC.

Joe Astrino also brings up a great point if this was running over a
frame relay switch in hub/spoke. All these types of issues can be
learned through Advanced Tech Classes by top vendors. It stuck out
like a sore thumb to me because of completing the Cisco 360 CIERS2
mock lab training. I have also seen this in videos from INE.

Just keep banging away at it. Learning the hard way on the CLI is how
it sticks. There are plenty of great resources in group study who like
to help (actually some of the best.... me not included). For me
trouble shooting and answering posts helps keep skills sharp as I
round the corner for my first lab attempt.

Keep up the good work and enjoy the voyage!

Marc Edwards - DCNISS
http://reno-ccie.blogspot.com
http://cisco-voyage.blogspot.com

On Sat, Jun 18, 2011 at 4:25 AM, Jules Eyabane <jep7619_at_gmail.com> wrote:
> Folks,
> Thanks All of You! the network type on the loopback was the culprit. once i
> changed the network type from loopback to point-to-point, the pings went
> through like a knife in butter!!!!!
> By the way, these are daisy-chained routers with frame-relay encap on the
> interfaces, but no frame relay switch in between, so no hub spoke here.
> so the bigger question is how does one troubleshoot this issue, unless
> you've ever ran into it? there was no debug command that could have made the
> issue obvious at all. debug icmp showed the packet leaving R2, while the
> problem was happening.
>
> Thanks anyway. you made my weekend!!!!!
>
> Jep.
>
> On Sat, Jun 18, 2011 at 12:24 AM, marc edwards <renorider_at_gmail.com> wrote:
>>
>> This appears to be just daisy chained routers with no Frame switch in
>> the middle. Not sure if hub spoke issues apply... My two cents is the
>> possibility that the prefix is being advertised as host and killing
>> look up. What happens if you advertise the lo0 of R4 with real network
>> address by adding - ip ospf network type point-to-point - under the
>> lo0 interface of R4?
>>
>> R2-PE#sho mpls forwarding-table
>> Local Outgoing Prefix Bytes tag Outgoing Next Hop
>> tag tag or VC or Tunnel Id switched interface
>> 200 300 4.4.4.4/32 0 Se0/0 point2point
>>
>> On Fri, Jun 17, 2011 at 7:41 PM, Jules Eyabane <jep7619_at_gmail.com> wrote:
>> > i have the following setup:
>> >
>> > R1----R2---R3---R4---R5
>> >
>> > R1 and R5 are CE routers
>> > R2 and R4 are PE routers
>> > R3 is a P router
>> >
>> > i have OSPF running as the underlining IGP between R2, R3 and R4, then i
>> > have MP-BGP running between the 2 PEs (R2 and R4)
>> > CE R1 uses EIGRP as the routing protocol of choice with PE R2, and CE R5
>> > uses RIP to talk to PE R4.
>> > LDP configured across R2, R3 and R4.
>> > Single VRF called HOME on both PEs.
>> > Routes are propagating across the PEs fine, but when from R1 between R5
>> > (sourcing from known ip to the remote end), it fails. So i moved closer
>> > and
>> > attempted ping between R2 and R4. fails too.
>> > On R2, R4's loopback (4.4.4.4) is listed as the next hop to all routes
>> > beyond it. But recursive lookup on 4.4.4.4 from R2's VRF CEF and LFIB
>> > tables
>> > fail
>> >
>> > Any suggestions would be appreciated!!!
>> >
>> > Some outputs below:
>> >
>> > R2-PE#sho ip bgp vpnv4 all
>> > BGP table version is 67, local router ID is 2.2.2.2
>> > Status codes: s suppressed, d damped, h history, * valid, > best, i -
>> > internal,
>> > r RIB-failure, S Stale
>> > Origin codes: i - IGP, e - EGP, ? - incomplete
>> >
>> > Network Next Hop Metric LocPrf Weight Path
>> > Route Distinguisher: 12:0 (default for vrf HOME)
>> > *> 1.0.0.0 10.1.12.1 409600 32768 ?
>> > *>i5.0.0.0 4.4.4.4 5 100 0 ?
>> > *> 10.1.12.0/24 0.0.0.0 0 32768 ?
>> > *>i10.1.45.0/24 4.4.4.4 0 100 0 ?
>> > *> 11.0.0.0 10.1.12.1 409600 32768 ?
>> > *> 22.0.0.0 0.0.0.0 0 32768 ?
>> > *>i44.0.0.0 4.4.4.4 0 100 0 ?
>> > *>i55.0.0.0 4.4.4.4 5 100 0 ?
>> > R2-PE#sho mpls ld
>> > R2-PE#sho mpls ldp bin
>> > R2-PE#sho mpls ldp bindings
>> > tib entry: 2.0.0.0/8, rev 6
>> > local binding: tag: imp-null
>> > tib entry: 2.2.2.2/32, rev 17
>> > remote binding: tsr: 3.3.3.3:0, tag: 301
>> > tib entry: 3.0.0.0/8, rev 15
>> > remote binding: tsr: 3.3.3.3:0, tag: imp-null
>> > tib entry: 3.3.3.3/32, rev 12
>> > local binding: tag: 201
>> > tib entry: 4.4.4.4/32, rev 10
>> > local binding: tag: 200
>> > remote binding: tsr: 3.3.3.3:0, tag: 300
>> > tib entry: 10.1.23.0/24, rev 4
>> > local binding: tag: imp-null
>> > remote binding: tsr: 3.3.3.3:0, tag: imp-null
>> > tib entry: 10.1.34.0/24, rev 14
>> > local binding: tag: 202
>> > remote binding: tsr: 3.3.3.3:0, tag: imp-null
>> > tib entry: 33.0.0.0/8, rev 16
>> > remote binding: tsr: 3.3.3.3:0, tag: imp-null
>> > R2-PE#sho mpls
>> > R2-PE#sho mpls for
>> > R2-PE#sho mpls forwarding-table
>> > Local Outgoing Prefix Bytes tag Outgoing Next Hop
>> > tag tag or VC or Tunnel Id switched interface
>> > 200 300 4.4.4.4/32 0 Se0/0 point2point
>> > 201 Untagged 3.3.3.3/32 0 Se0/0 point2point
>> > 202 Pop tag 10.1.34.0/24 0 Se0/0 point2point
>> > 204 Aggregate 22.0.0.0/8[V] 0
>> > 205 Aggregate 10.1.12.0/24[V] 0
>> > 207 Untagged 1.0.0.0/8[V] 0 Fa0/0 10.1.12.1
>> > 208 Untagged 11.0.0.0/8[V] 0 Fa0/0 10.1.12.1
>> > R2-PE#sho ip route vr
>> > R2-PE#sho ip route vrf HOME
>> >
>> > Routing Table: HOME
>> > Codes: C - connected, S - static, R - RIP, M - mobile, B - BGP
>> > D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
>> > N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
>> > E1 - OSPF external type 1, E2 - OSPF external type 2
>> > i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS
>> > level-2
>> > ia - IS-IS inter area, * - candidate default, U - per-user static
>> > route
>> > o - ODR, P - periodic downloaded static route
>> >
>> > Gateway of last resort is not set
>> >
>> > D 1.0.0.0/8 [90/409600] via 10.1.12.1, 01:39:24, FastEthernet0/0
>> > B 55.0.0.0/8 [200/5] via 4.4.4.4, 00:34:25
>> > B 5.0.0.0/8 [200/5] via 4.4.4.4, 00:34:25
>> > C 22.0.0.0/8 is directly connected, Loopback11
>> > 10.0.0.0/24 is subnetted, 2 subnets
>> > C 10.1.12.0 is directly connected, FastEthernet0/0
>> > B 10.1.45.0 [200/0] via 4.4.4.4, 00:34:25
>> > D 11.0.0.0/8 [90/409600] via 10.1.12.1, 01:39:25, FastEthernet0/0
>> > B 44.0.0.0/8 [200/0] via 4.4.4.4, 00:34:25
>> > R2-PE#sho ip int brief
>> > Interface IP-Address OK? Method Status
>> > Protocol
>> > FastEthernet0/0 10.1.12.2 YES manual up
>> > up
>> > Serial0/0 10.1.23.2 YES NVRAM up
>> > up
>> > FastEthernet0/1 unassigned YES NVRAM administratively
>> > down
>> > down
>> > Serial0/1 unassigned YES NVRAM administratively
>> > down
>> > down
>> > Loopback0 2.2.2.2 YES NVRAM up
>> > up
>> > Loopback11 22.2.2.2 YES manual up
>> > up
>> > R2-PE#ping vr
>> > R2-PE#ping vrf HOME 10.1.45.4 sou
>> > R2-PE#ping vrf HOME 10.1.45.4 source loo11
>> >
>> > Type escape sequence to abort.
>> > Sending 5, 100-byte ICMP Echos to 10.1.45.4, timeout is 2 seconds:
>> > Packet sent with a source address of 22.2.2.2
>> > .....
>> > Success rate is 0 percent (0/5)
>> >
>> > ======================
>> > R2's config below
>> >
>> > hostname R2-PE
>> > !
>> > boot-start-marker
>> > boot-end-marker
>> > !
>> > !
>> > no aaa new-model
>> > memory-size iomem 5
>> > ip cef
>> > !
>> > ip vrf HOME
>> > rd 12:0
>> > route-target export 24:24
>> > route-target import 42:42
>> > !
>> > no ip domain lookup
>> > !
>> > mpls label range 200 299
>> > mpls label protocol ldp
>> > multilink bundle-name authenticated
>> > !
>> > !!
>> > !
>> > archive
>> > log config
>> > hidekeys
>> > !
>> > !
>> > interface Loopback0
>> > ip address 2.2.2.2 255.0.0.0
>> > !
>> > interface Loopback11
>> > ip vrf forwarding HOME
>> > ip address 22.2.2.2 255.0.0.0
>> > !
>> > interface FastEthernet0/0
>> > ip vrf forwarding HOME
>> > ip address 10.1.12.2 255.255.255.0
>> > duplex auto
>> > speed auto
>> > !
>> > interface Serial0/0
>> > ip address 10.1.23.2 255.255.255.0
>> > mpls ip
>> > clock rate 2000000
>> > !
>> > interface FastEthernet0/1
>> > no ip address
>> > shutdown
>> > duplex auto
>> > speed auto
>> > !
>> > interface Serial0/1
>> > no ip address
>> > shutdown
>> > clock rate 2000000
>> > !
>> > router eigrp 22
>> > no auto-summary
>> > !
>> > address-family ipv4 vrf HOME
>> > redistribute bgp 6500 metric 1 1 1 1 1
>> > network 10.1.12.0 0.0.0.255
>> > network 22.2.2.0 0.0.0.255
>> > no auto-summary
>> > autonomous-system 12
>> > eigrp router-id 2.2.2.2
>> > exit-address-family
>> > eigrp router-id 2.2.2.2
>> > !
>> > router ospf 1
>> > router-id 2.2.2.2
>> > log-adjacency-changes
>> > network 2.2.2.2 0.0.0.0 area 0
>> > network 10.1.23.0 0.0.0.255 area 0
>> > !
>> > router bgp 6500
>> > no bgp default ipv4-unicast
>> > bgp log-neighbor-changes
>> > neighbor 4.4.4.4 remote-as 6500
>> > neighbor 4.4.4.4 update-source Loopback0
>> > !
>> > address-family vpnv4
>> > neighbor 4.4.4.4 activate
>> > neighbor 4.4.4.4 send-community both
>> > exit-address-family
>> > !
>> > address-family ipv4 vrf HOME
>> > redistribute eigrp 12
>> > no synchronization
>> > exit-address-family
>> > !
>> > ip forward-protocol nd
>> > !
>> > !
>> > ip http server
>> > no ip http secure-server
>> > !
>> > access-list 1 permit 4.4.4.4
>> > !
>> > !!
>> > mpls ldp router-id Loopback0
>> > !
>> >
>> >
>> >
>> > =======================
>> > R4's config below
>> > hostname R4-PE
>> > !
>> > boot-start-marker
>> > boot-end-marker
>> > !
>> > !
>> > no aaa new-model
>> > memory-size iomem 5
>> > ip cef
>> > !
>> > ip vrf HOME
>> > rd 12:0
>> > route-target export 42:42
>> > route-target import 24:24
>> > !
>> > no ip domain lookup
>> > !
>> > mpls label range 400 499
>> > mpls label protocol ldp
>> > multilink bundle-name authenticated
>> > !
>> >
>> > archive
>> > log config
>> > hidekeys
>> > !
>> >
>> > interface Loopback0
>> > ip address 4.4.4.4 255.0.0.0
>> > !
>> > interface Loopback11
>> > ip vrf forwarding HOME
>> > ip address 44.4.4.4 255.0.0.0
>> > !
>> > interface FastEthernet0/0
>> > ip vrf forwarding HOME
>> > ip address 10.1.45.4 255.255.255.0
>> > duplex auto
>> > speed auto
>> > !
>> > interface Serial0/0
>> > no ip address
>> > shutdown
>> > clock rate 2000000
>> > !
>> > interface FastEthernet0/1
>> > no ip address
>> > shutdown
>> > duplex auto
>> > speed auto
>> > !
>> > interface Serial0/1
>> > ip address 10.1.34.4 255.255.255.0
>> > mpls ip
>> > clock rate 2000000
>> > !
>> > router ospf 1
>> > router-id 4.4.4.4
>> > log-adjacency-changes
>> > network 4.4.4.4 0.0.0.0 area 0
>> > network 10.1.34.0 0.0.0.255 area 0
>> > !
>> > router ospf 4
>> > router-id 10.1.45.4
>> > log-adjacency-changes
>> > network 10.1.45.0 0.0.0.255 area 45
>> > !
>> > router rip
>> > version 2
>> > passive-interface default
>> > no passive-interface FastEthernet0/0
>> > no passive-interface Loopback0
>> > no auto-summary
>> > !
>> > address-family ipv4 vrf HOME
>> > redistribute bgp 6500 metric 5
>> > network 4.0.0.0
>> > network 10.0.0.0
>> > network 44.0.0.0
>> > no auto-summary
>> > version 2
>> > exit-address-family
>> > !
>> > router bgp 6500
>> > no bgp default ipv4-unicast
>> > bgp log-neighbor-changes
>> > neighbor 2.2.2.2 remote-as 6500
>> > neighbor 2.2.2.2 update-source Loopback0
>> > !
>> > address-family vpnv4
>> > neighbor 2.2.2.2 activate
>> > neighbor 2.2.2.2 send-community both
>> > exit-address-family
>> > !
>> > address-family ipv4 vrf HOME
>> > redistribute rip metric 5
>> > no synchronization
>> > exit-address-family
>> >
>> >
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>> >
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Received on Sat Jun 18 2011 - 06:58:48 ART