cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
494
Views
2
Helpful
17
Replies

MPLS VPN VRF route selection

jain.manish94
Spotlight
Spotlight

Hello Team, 

need your help to understand the route selection when we using MPLS and inside the MPLS there is OSPF protocol. I am getting confuse when doing traceroute from CE1 to CE2 another site and it is taking the path which i am not understanding. 

Please find my gns diagram. 

in this attached topology all are working fine there is no issue. but below is my question. 

when i am doing traceroute. from CE-1-GOA to CE-2-GOA Loopback ip address without source, it is taking other path but when using same traceroute with source it is taking another path. why here i am getting confused. 

CE1-GOA#traceroute 22.22.22.22
Type escape sequence to abort.
Tracing the route to 22.22.22.22
VRF info: (vrf in name/id, vrf out name/id)
1 192.168.2.254 120 msec 172 msec 216 msec
2 192.168.4.1 [MPLS: Labels 16/22 Exp 0] 784 msec 812 msec 900 msec
3 192.168.8.254 [MPLS: Label 22 Exp 0] 596 msec 728 msec 504 msec
4 192.168.8.1 688 msec 628 msec 628 msec

 

 

CE1-GOA#traceroute 22.22.22.22 source lo0
Type escape sequence to abort.
Tracing the route to 22.22.22.22
VRF info: (vrf in name/id, vrf out name/id)
1 192.168.2.254 228 msec 132 msec 212 msec
2 192.168.3.1 [MPLS: Labels 16/22 Exp 0] 752 msec 788 msec 588 msec
3 192.168.8.254 [MPLS: Label 22 Exp 0] 532 msec 484 msec 524 msec
4 192.168.8.1 576 msec 632 msec 896 msec

17 Replies 17

Show ip route in both CE 

Show run in both CE 

Share above 

MHM

CE2#traceroute 20.20.20.20

Type escape sequence to abort.
Tracing the route to 20.20.20.20

1 192.168.2.1 36 msec 36 msec 32 msec
2 192.168.5.254 [MPLS: Labels 500/204 Exp 0] 132 msec 136 msec 132 msec
3 192.168.4.1 [MPLS: Label 204 Exp 0] 100 msec 100 msec 100 msec
4 192.168.4.2 132 msec 136 msec 132 msec

CE2#show ip route
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

100.0.0.0/32 is subnetted, 2 subnets
C 100.100.100.100 is directly connected, Loopback0
O E2 100.100.100.101 [110/65] via 192.168.2.1, 00:00:42, Serial1/1
98.0.0.0/24 is subnetted, 1 subnets
O E2 98.98.98.0 [110/5064] via 192.168.2.1, 00:00:42, Serial1/1
20.0.0.0/32 is subnetted, 1 subnets
O E2 20.20.20.20 [110/65] via 192.168.2.1, 00:00:42, Serial1/1
172.168.0.0/32 is subnetted, 1 subnets
C 172.168.1.1 is directly connected, Loopback2
O E2 192.168.4.0/24 [110/1] via 192.168.2.1, 00:00:42, Serial1/1
10.0.0.0/32 is subnetted, 1 subnets
C 10.10.10.10 is directly connected, Loopback1
C 192.168.2.0/24 is directly connected, Serial1/1

CE2#show running-config
Building configuration...

Current configuration : 2220 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname CE2
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Loopback0
ip address 100.100.100.100 255.255.255.255
!
interface Loopback1
ip address 10.10.10.10 255.255.255.255
!
interface Loopback2
ip address 172.168.1.1 255.255.255.255
ip ospf network point-to-point
!
interface FastEthernet0/0
no ip address
shutdown
duplex half
!
interface Serial1/0
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/1
ip address 192.168.2.2 255.255.255.0
serial restart-delay 0
!
interface Serial1/2
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/3
no ip address
shutdown
serial restart-delay 0
!
interface FastEthernet2/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet2/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet3/0
ip address 98.98.98.1 255.255.255.0
ip ospf cost 5000
shutdown
duplex half
!
interface Ethernet3/1
no ip address
shutdown
duplex half
!
interface Ethernet3/2
no ip address
shutdown
duplex half
!
interface Ethernet3/3
no ip address
shutdown
duplex half
!
interface GigabitEthernet4/0
no ip address
shutdown
negotiation auto
!
interface FastEthernet5/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet5/1
no ip address
shutdown
duplex auto
speed auto
!
router ospf 100
log-adjacency-changes
network 10.10.10.10 0.0.0.0 area 0
network 98.98.98.0 0.0.0.255 area 0
network 100.100.100.100 0.0.0.0 area 0
network 192.168.2.0 0.0.0.255 area 0
!
!
no ip http server
no ip http secure-server
!
!
!
ip prefix-list test seq 5 permit 172.168.1.1/32
no cdp log mismatch duplex
!
route-map test permit 10
match ip address prefix-list test
!
!
!
!
control-plane
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line vty 0 4
login
!
!
end

 

PE-1#show ip route vrf CUST-B

Routing Table: CUST-B
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

100.0.0.0/32 is subnetted, 2 subnets
O 100.100.100.100 [110/65] via 192.168.2.2, 00:02:27, Serial1/1
B 100.100.100.101 [200/65] via 22.22.22.22, 00:03:54
98.0.0.0/24 is subnetted, 1 subnets
B 98.98.98.0 [200/5064] via 22.22.22.22, 00:03:54
20.0.0.0/32 is subnetted, 1 subnets
B 20.20.20.20 [200/65] via 22.22.22.22, 00:03:54
B 192.168.4.0/24 [200/0] via 22.22.22.22, 00:03:54
10.0.0.0/32 is subnetted, 1 subnets
O 10.10.10.10 [110/65] via 192.168.2.2, 00:02:27, Serial1/1
C 192.168.2.0/24 is directly connected, Serial1/1

PE-1#show running-config | section router bgp
router bgp 500
bgp router-id 11.11.11.11
no bgp default ipv4-unicast
bgp log-neighbor-changes
neighbor 22.22.22.22 remote-as 500
neighbor 22.22.22.22 update-source Loopback0
!
address-family vpnv4
neighbor 22.22.22.22 activate
neighbor 22.22.22.22 send-community extended
neighbor 22.22.22.22 next-hop-self
exit-address-family
!
address-family ipv4 vrf CUST-B
redistribute ospf 100 vrf CUST-B match internal external 1 external 2
no synchronization
exit-address-family
!
address-family ipv4 vrf CUST-A
neighbor 192.168.1.2 remote-as 65500
neighbor 192.168.1.2 activate
neighbor 192.168.1.2 as-override
no synchronization
exit-address-family

PE-1#show running-config | section router ospf
router ospf 100 vrf CUST-B
log-adjacency-changes
redistribute bgp 500 subnets
network 192.168.2.0 0.0.0.255 area 0
router ospf 500
log-adjacency-changes
network 11.11.11.11 0.0.0.0 area 0
network 192.168.5.0 0.0.0.255 area 0

 

CE2-1#traceroute 10.10.10.10

Type escape sequence to abort.
Tracing the route to 10.10.10.10

1 192.168.4.1 20 msec 32 msec 32 msec
2 192.168.6.254 [MPLS: Labels 501/104 Exp 0] 168 msec 132 msec 140 msec
3 192.168.2.1 [MPLS: Label 104 Exp 0] 100 msec 100 msec 100 msec
4 192.168.2.2 132 msec 128 msec 132 msec
CE2-1#sho
CE2-1#show ip rou
CE2-1#show ip route
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

100.0.0.0/32 is subnetted, 2 subnets
O E2 100.100.100.100 [110/65] via 192.168.4.1, 00:03:39, Serial1/2
C 100.100.100.101 is directly connected, Loopback0
98.0.0.0/24 is subnetted, 1 subnets
C 98.98.98.0 is directly connected, Ethernet3/0
20.0.0.0/32 is subnetted, 1 subnets
C 20.20.20.20 is directly connected, Loopback1
C 192.168.4.0/24 is directly connected, Serial1/2
10.0.0.0/32 is subnetted, 1 subnets
O E2 10.10.10.10 [110/65] via 192.168.4.1, 00:03:39, Serial1/2
O E2 192.168.2.0/24 [110/1] via 192.168.4.1, 00:04:34, Serial1/2

 

PE-2#show running-config | section router bgp
router bgp 500
no bgp default ipv4-unicast
bgp log-neighbor-changes
neighbor 11.11.11.11 remote-as 500
neighbor 11.11.11.11 update-source Loopback0
!
address-family vpnv4
neighbor 11.11.11.11 activate
neighbor 11.11.11.11 send-community extended
neighbor 11.11.11.11 next-hop-self
exit-address-family
!
address-family ipv4 vrf CUST-B
redistribute ospf 200 vrf CUST-B match internal external 1 external 2
no synchronization
exit-address-family
!
address-family ipv4 vrf CUST-A
neighbor 192.168.3.2 remote-as 65501
neighbor 192.168.3.2 activate
no synchronization
exit-address-family
PE-2#show running-config | section router ospf
router ospf 200 vrf CUST-B
log-adjacency-changes
redistribute bgp 500 subnets
network 192.168.4.0 0.0.0.255 area 0
router ospf 500
log-adjacency-changes
network 22.22.22.22 0.0.0.0 area 0
network 192.168.6.0 0.0.0.255 area 0

 

 

CE2-1#show running-config
Building configuration...

Current configuration : 2066 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname CE2-1
!
boot-start-marker
boot-end-marker
!
!
no aaa new-model
no ip icmp rate-limit unreachable
!
!
ip cef
no ip domain lookup
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
ip tcp synwait-time 5
!
!
!
!
!
interface Loopback0
ip address 100.100.100.101 255.255.255.255
ip ospf 200 area 0
!
interface Loopback1
ip address 20.20.20.20 255.255.255.255
ip ospf 200 area 0
!
interface FastEthernet0/0
no ip address
shutdown
duplex half
!
interface Serial1/0
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/1
no ip address
shutdown
serial restart-delay 0
!
interface Serial1/2
ip address 192.168.4.2 255.255.255.0
serial restart-delay 0
!
interface Serial1/3
no ip address
shutdown
serial restart-delay 0
!
interface FastEthernet2/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet2/1
no ip address
shutdown
duplex auto
speed auto
!
interface Ethernet3/0
ip address 98.98.98.2 255.255.255.0
ip ospf cost 5000
ip ospf 200 area 0
duplex half
!
interface Ethernet3/1
no ip address
shutdown
duplex half
!
interface Ethernet3/2
no ip address
shutdown
duplex half
!
interface Ethernet3/3
no ip address
shutdown
duplex half
!
interface GigabitEthernet4/0
no ip address
shutdown
negotiation auto
!
interface FastEthernet5/0
no ip address
shutdown
duplex auto
speed auto
!
interface FastEthernet5/1
no ip address
shutdown
duplex auto
speed auto
!
router ospf 200
log-adjacency-changes
network 20.20.20.20 0.0.0.0 area 0
network 98.98.98.0 0.0.0.255 area 0
network 100.100.100.101 0.0.0.0 area 0
network 192.168.4.0 0.0.0.255 area 0
!
!
no ip http server
no ip http secure-server
!
!
no cdp log mismatch duplex
!
!
!
!
control-plane
!
!
!
!
!
!
gatekeeper
shutdown
!
!
line con 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line aux 0
exec-timeout 0 0
privilege level 15
logging synchronous
stopbits 1
line vty 0 4
login
!
!
end

 

 

 

 

I run lab and use different and same processes and dont use match internal or external in redistrubte

It seem that it IOS command limitations.

MHM

Screenshot (402).pngScreenshot (403).pngScreenshot (404).pngScreenshot (398).pngScreenshot (400).png

Review Cisco Networking for a $25 gift card