12.2 31 SB13 Internet VRF Issue...Continued

Finally I got time to write findings on 12.2 31 SB12. Findings covered the problem faced in Inter VRF Leaking.

Introduction
A weird problem faced with 12.2(31)SB13 series. I made a test best in which R2 is working as upstream service provider which is providing internet services to other service providers. R1 router is another service provider router which is injecting a default route towards the R2. R1 router service provider is having MPLSVPN network and also serving internet services to the customers. R1 is having two number of vrfs one is INTERNET and another is CUST. RT of INTERNET vrf is imported in CUST vrf so that CUST vrf is able to access the internet cloud. But when a ping is initiated from R0 which is working as CE I found the given results:-



Results After Testing (See Figure 1 For Setup)Results of CE Ping
CE# ping 4.2.2.2 source loopback 0
Sending 5, 100-byte ICMP Echos to 4.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 3.1.1.1
.....
Success rate is 0 percent (0/5)

INTERNET_MPLS# show ip bgp vpnv4 vrf CUST
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 1:1 (default for vrf CUST)
*> 0.0.0.0 1.1.1.1 0 32768 i
*> 2.2.2.0/30 0.0.0.0 0 32768 ?

INTERNET_MPLS# show mpls forwarding-table vrf INTERNET 0.0.0.0
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or VC or Tunnel Id Switched interface
None No Label 0.0.0.0/32[V] 0 aggr-punt/INTERNET


Customer is not able to reach to the internet. Thereafter for test my scenario I simple remove the INTERNET RT from CUST vrf and leak the default route in CUST vrf instead of vrf INTERNET.

Given Route Added
ip route vrf CUST 0.0.0.0 0.0.0.0 1.1.1.1 global

CE# ping 4.2.2.2 source loopback 0
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 4.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 3.1.1.1
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 116/315/544 ms

Note:- Need to add 0.0.0.0 with the help of network command under address family of vrf else the route won’t come in the vrf routing table because the next hop is available in global routing table not in vrf table.

INTERNET_MPLS# show ip bgp vpnv4 vrf CUST
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 1:1 (default for vrf CUST)
*> 0.0.0.0 1.1.1.1 0 32768 i
*> 2.2.2.0/30 0.0.0.0 0 32768 ?

INTERNET_MPLS# show mpls forwarding-table vrf CUST 0.0.0.0
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or VC or Tunnel Id Switched interface
None No Label 0.0.0.0/32[V] 0 aggr-punt/CUST


IOS Changed To 12.4 15 T1



Now I changed the IOS of R1 to 12.4 15 T1 and was able to serve internet to esteemed customers. Below are the findings after adding 12.4 15T1 to R1

Results of CE Ping
CE# ping 4.2.2.2 source loopback 0
Sending 5, 100-byte ICMP Echos to 4.2.2.2, timeout is 2 seconds:
Packet sent with a source address of 3.1.1.1
!!!!!
Success rate is 100 percent (5/5)

INTERNET_MPLS# show ip bgp vpnv4 vrf CUST
Network Next Hop Metric LocPrf Weight Path
Route Distinguisher: 1:1 (default for vrf CUST)
*> 0.0.0.0 1.1.1.1 0 32768 i
*> 2.2.2.0/30 0.0.0.0 0 32768 ?

INTERNET_MPLS#sh mpls forwarding-table vrf CUST 0.0.0.0 0
Local Outgoing Prefix Bytes tag Outgoing Next Hop
tag tag or VC or Tunnel Id switched interface
None Untagged 0.0.0.0/0 0 Fa0/0 1.1.1.1

Findings After Adding 12.2 31 SB13a) If the same router is advertising a default route and customers vrf are coming onto the same router in that case SB 13 is not able to serve internet to customers.
b) If default route is leaked in customer vrf then customer is able to surf internet.
c) If the default route is announced on another router except SB13, In that case internet works fine. See Figure 3



What My Thought Process Says
SB13 is not able to convert vpn traffic to ip traffic on the same router. Because in my scenario customer is forwarding ip traffic and R1 is receiving in the vrf and on the same router it converts the vpnv4 traffic to ip traffic and consequence customer is not able to surf internet. But if the default route shifted to another PE and SB13 route forwards the VPNv4 traffic till that router and thereafter traffic is converted to ip traffic and everything works fine.

Workaround
Either change the IOS or shift the default route to somewhere else so that till that VPN label will be swapped and thereafter traffic will be converted to ip traffic.


regards
shivlu jain

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