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On Lab 2, I am having issues with getting MPLS to cross my PPPoE connection.  Section 1.6 is setting up a PPPoE link between R5 and R6.  I set this up and the PPPoE connection is up and good.  My configs pretty well match the solutions guide, and all is good initially, but I set up my MP-eBGP (address-family vpnv4) session which makes R5 and R6 direct MP-eBGP neighbors.  They are ASBRs (option B), but my underlying link does not get enabled for MPLS which it should by default. 

With PPPoE link up between R5 and R6...
--------------------------
r5#show mpls interfaces
Interface              IP            Tunnel   Operational
FastEthernet0/0        Yes (ldp)     No       Yes        
r5#

r6#show mpls interfaces
Interface              IP            Tunnel   Operational
GigabitEthernet0/1     Yes (ldp)     No       Yes        
r6#

if I remove the PPPoE and just run this over the Ethernet connection between R5 and R6, everything runs smoothly and the BGP sessions automatically enables MPLS on the underlying interfaces as it should.
--------------------------
r5#show mpls interfaces
Interface              IP            Tunnel   Operational
FastEthernet0/0        Yes (ldp)     No       Yes        
FastEthernet0/1        No            No       Yes        
r5#

r6#show mpls interfaces
Interface              IP            Tunnel   Operational
GigabitEthernet0/0     No            No       Yes        
GigabitEthernet0/1     Yes (ldp)     No       Yes        
r6#

I have also enabled a tunnel interface over the PPPoE link, and that does work.  It works pretty much the same as if I were running direct over the ethernet interfaces.  I am not sure what I am missing about PPPoE and running your MP-eBGP/MPLS over it. 

I have tried to enable the ip tcp adjust-mss 1452 and tag-switching mtu 1452 with the PPPoE, but no luck.  Any help is appreciated.

- jeff

Show us your configs on interfaces and bgp. What IOS do you use?

Cheers,

Seba

Seba,

Here are the relevant configs for R5 and R6. 

R5#s run
!
version 12.3
!
hostname r5
!
ip subnet-zero
ip cef
!
mpls label protocol ldp
mpls ldp neighbor 158.1.4.4 password CISCO
tag-switching tdp router-id Loopback0
!
username AS100 password 0 CISCO
!
interface Loopback0
 ip address 158.1.5.5 255.255.255.255
!
interface FastEthernet0/1
 duplex auto
 speed auto
 pppoe enable
 pppoe-client dial-pool-number 56
!
interface Dialer56
 mtu 1492
 bandwidth 100000
 ip address 24.1.56.5 255.255.255.0
 encapsulation ppp
 dialer pool 56
 dialer persistent
 ppp authentication chap
 ppp chap hostname AS200
 ppp chap password 0 CISCO
!
router isis
 net 49.00c8.0000.9e01.0505.00
 log-adjacency-changes all
 passive-interface Loopback0
!
router bgp 200
 no bgp default ipv4-unicast
 no bgp default route-target filter
 bgp log-neighbor-changes
 neighbor AS200 peer-group
 neighbor AS200 remote-as 200
 neighbor AS200 update-source Loopback0
 neighbor 24.1.56.6 remote-as 100
 neighbor 158.1.4.4 peer-group AS200
 !
 address-family ipv4
 redistribute connected route-map CONNECTED
 redistribute isis level-2 route-map IPv4_ISIS_to_BGP
 neighbor AS200 next-hop-self
 neighbor 24.1.56.6 activate
 neighbor 158.1.4.4 activate
 no auto-summary
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor AS200 send-community extended
 neighbor AS200 next-hop-self
 neighbor 24.1.56.6 activate
 neighbor 24.1.56.6 send-community extended
 neighbor 158.1.4.4 activate
 exit-address-family
!
end

r5#
----------------------------------------------------------
r6#s run
!
version 12.3
!
hostname r6
!
username AS200 password 0 CISCO
!
ip subnet-zero
ip cef
!
vpdn enable
!
vpdn-group PPPoE
 accept-dialin
  protocol pppoe
  virtual-template 65
!
mpls label protocol ldp
tag-switching tdp router-id Loopback0
!
interface Loopback0
 ip address 158.1.6.6 255.255.255.255
!
interface GigabitEthernet0/0
 duplex auto
 speed auto
 media-type rj45
 pppoe enable
!
interface Virtual-Template65
 ip address 24.1.56.6 255.255.255.0
 ppp authentication chap
 ppp chap hostname AS100
 ppp chap password 0 CISCO
!
router isis
 net 49.0064.0000.9e01.0606.00
 log-adjacency-changes all
 passive-interface Loopback0
!
router bgp 100
 no bgp default ipv4-unicast
 no bgp default route-target filter
 bgp log-neighbor-changes
 neighbor AS100 peer-group
 neighbor AS100 remote-as 100
 neighbor AS100 update-source Loopback0
 neighbor 24.1.56.5 remote-as 200
 neighbor 54.1.2.254 remote-as 54
 neighbor 158.1.3.3 peer-group AS100
 !
 address-family ipv4
 redistribute connected route-map CONNECTED
 redistribute isis level-2 route-map IPv4_ISIS_to_BGP
 neighbor AS100 activate
 neighbor AS100 next-hop-self
 neighbor 24.1.56.5 activate
 neighbor 54.1.2.254 activate
 neighbor 158.1.3.3 peer-group AS100
 no auto-summary
 no synchronization
 exit-address-family
 !
 address-family vpnv4
 neighbor AS100 activate
 neighbor AS100 next-hop-self
 neighbor AS100 send-community extended
 neighbor 24.1.56.5 activate
 neighbor 24.1.56.5 send-community extended
 neighbor 158.1.3.3 peer-group AS100
 exit-address-family
!
end

r6#

I just simulated similar setup (not a whole lab) and everything works fine.

I used 2*3745, C3745-ADVENTERPRISEK9-M), Version 12.4(15)T1 on dynamips.

One difference in configuration on Virtual-Template1:

 no peer neighbor-route

Everything else is exactly the same (I use different IP and BGP AS numbers, but it really doesn't' matter)

EDIT: I just cleared BGP session (hardcore cle ip bgp *) and I don't  see anything in "show mpls interface" anymore, but InterAS VPN seems to fine as I can ping between defined interface in VRFs

Interesting, probably IOS feature ;) I did this lab a few months ago, so I don't exactly remember my solution and I don't remember if I was able to see something in "sh mpls int" or not.

Cheers,

Seba

Seba,
Thanks for the response.  I went ahead and tested with the no peer neighbor-route just to remove that difference.  I am still having the same issue.  I would have to agree with you at this point it appears to be an IOS feature ;). 

I tried to keep the gear a close to the versions in the blue print as possible.  My R5 is a 3640 with 12.3(14)T7 and R6 is a 3845 with 12.3(11)T3.  I am going to investigate alternate IOS images at a later date, probably a 12.4T image as you tested with.  Good to hear yours was working.

Regards,
-Jeff

For those of you who are curious.  I have found that the version of IOS I was using was the culprit as Seba pointed out.  What I found was that the configuration side with the virtual-template (r6 in the above case) was behaving correctly, however the side with the Dialer interface (r5 in the above case), was getting the labels correctly in BGP, and everything seemed good there, however the labels it was getting via BGP were not being placed into the mpls forwarding table.  For whatever it is worth if anyone else runs across a similar issue with 12.3T, I would suggest going to a 12.4 or 12.4T code.