MPLS Config

Question

I want to create one scenario using L3 VPN MPLS.Can any one tell me what config is require on R1,R2,R3,R4 in MPLS cloud.
So that i can ping CE2 from CE1.
Pls find the attachment.
Thanx.....

Answer 1

Hello Arjun,
the following steps are required:
a) building the network infrastructure using an IGP: for example OSPF
Allocate /32 loopbacks on all R1-R4.
For example:
Ri : Loop0 ip address 10.250.250.i/32
int loop0
ip address 10.250.250.i 255.255.255.255
desc loop used as LDP router-id, BGP RID
network infrastructure:
let's suppose we use 10.10.10.0/24 with subnettting for all backbone links between R1-R4
OSPF config
router ospf 10
router-id 10.250.250.i
network 10.10.10.0 0.0.0.255 area 0
network 10.250.250.i 0.0.0.0 area 0
verify you can ping from loopback to loopback using extended ping
b) enable MPLS on all routers
ip cef
mpls ip
mpls label protocol ldp
mpls ldp router-id loop0 force
on all backbone interfaces with ip addresses in 10.10.10.0/24 add
int type x/y
mpls ip
verify again connectivity of loopbacks
verify with
sh mpls forwarding 10.250.250.i
what action is associated to each loopback
c) enable iBGP multiprotocol
let's use AS 65000
router bgp 65000
bgp router-id 10.250.250.i
no bgp default ipv4-unicast
neigh 10.250.250.j remote-as 65000
neigh 10.250.250.j update-source loop0
! do it for all three other routers
address-family vpnv4
neigh 10.250.250.j activate
neigh 10.250.250.j send-community both
! again do this for all three routers
use
sh ip bgp vpvn4 all summary to check
every router should see 0 prefixes from the other three
d) create the VRF
ip vrf TEST
rd 65000:101
route-target export 65000:1001
router-targer import 65000:1001
associate the link to CE with the VRF
int type x/y
ip vrf forwarding TEST
! caution you need to retype the ip address command as desired
router bgp 65000
address-family ipv4 vrf TEST
red connected
no sync
do this on both R1 and R2
now if you do
sh ip bgp v a s you should 1 prefix advertised by R1 and 1 by R2.
Note:
there can be some syntax errors
I wrote on the fly
Edit:
to be able to ping from LAN to LAN you need to decide how PE and CE should communicate.
the simplest solutions are:
static routes
or an eBGP session to be configured on the PE side under
router bgp 65000
address-family ipv4 vrf TEST
for static routes:
red static
for eBGP session:
neighbor CE-address remote-as 65200
for static routes the keyword vrf TEST has to be added to the command
Hope to help
Giuseppe