EoMPLS L2VPN Ethernet Port Mode to allow VLAN Rewrite

Hi,
Does anyone know how to configure VLAN rewrite for L2VPN EoMPLS to allow the two ACs to be in different VLANs?

I am trying to setup a EoMPLS scenario where CE1-PE1 are in one VLAN and CE2-PE2 are in another VLAN (i think its called VLAN rewrite). But I am not able to get IP connectivity b/w SW1 and SW2, instead the ports on switches go into STP BKN state, even if I use "interworking ethernet" which is supposed to strip off the VLAN tag

Network Setup:
! SW1-R1-R2-SW2, where SW1=CE1, SW2=CE2, R1=PE1, R2=PE2
! SW1-R1 AC is in VLAN 99
! SW2-R2 AC is in VLAN 100
! PW is b/w R1-R2 with "interworking ethernet"

!!!!!!!!!!!!!!!!!!!!!!! I have setup LDP+IGP b/w R1-R2
R1#show run | s router ospf
router ospf 1
 log-adjacency-changes
 network 0.0.0.0 255.255.255.255 area 0
 mpls ldp auto
R1#

R2#show run | s router ospf
router ospf 1
 log-adjacency-changes
 network 0.0.0.0 255.255.255.255 area 0
 mpls ldp auto
R2#

!!!!!!!!!!!!!!!!!!!!!!! SW1-R1 AC is in VLAN 99
SW1#show run int fa1/1
Building configuration...

Current configuration : 71 bytes
!
interface FastEthernet1/1
 switchport mode trunk
 no ip address
end

SW1#show run int vlan 99
Building configuration...

Current configuration : 59 bytes
!
interface Vlan99
 ip address 99.0.0.1 255.255.255.0
end

SW1#

R1#show run interface FastEthernet1/1.10
Building configuration...

Current configuration : 99 bytes
!
interface FastEthernet1/1.10
 encapsulation dot1Q 99
 xconnect 2.0.0.1 12 pw-class ethernet
end
R1#show run | s pseud
pseudowire-class ethernet
 encapsulation mpls
 interworking ethernet
R1#

!!!!!!!!!!!!!!!!!!!!!!! SW2-R2 AC is in VLAN 100
SW2# show run int fa1/1
Building configuration...

Current configuration : 71 bytes
!
interface FastEthernet1/1
 switchport mode trunk
 no ip address
end

SW2#show run int vlan 100
Building configuration...

Current configuration : 60 bytes
!
interface Vlan100
 ip address 99.0.0.2 255.255.255.0
end

SW2#

R2#show run interface FastEthernet1/1.10
Building configuration...

Current configuration : 99 bytes
!
interface FastEthernet1/1.10
 encapsulation dot1Q 99
 xconnect 1.0.0.1 12 pw-class ethernet
end
R2#show run | s pseud
pseudowire-class ethernet
 encapsulation mpls
 interworking ethernet
R2#


!!!!!!!!!!!!!!!!!!!!!!! PW is up and running
R1#show xconnect all
Legend:    XC ST=Xconnect State  S1=Segment1 State  S2=Segment2 State
  UP=Up       DN=Down            AD=Admin Down      IA=Inactive
  SB=Standby  HS=Hot Standby     RV=Recovering      NH=No Hardware

XC ST  Segment 1                         S1 Segment 2                         S2
------+---------------------------------+--+---------------------------------+--
UP     ac   Fa1/1.10:99(Eth VLAN)        UP mpls 2.0.0.1:12                   UP
R1#
R1#show mpls l2transport binding
  Destination Address: 2.0.0.1,  VC ID: 12
    Local Label:  18
        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
        MTU: 1500,   Interface Desc: n/a
        VCCV: CC Type: CW [1], RA [2], TTL [3]
              CV Type: LSPV [2]
    Remote Label: 16
        Cbit: 1,    VC Type: Ethernet,    GroupID: 0
        MTU: 1500,   Interface Desc: n/a
        VCCV: CC Type: CW [1], RA [2], TTL [3]
              CV Type: LSPV [2]
R1#
R1#ping mpls pseudowire 2.0.0.1 12
%Total number of MS-PW segments is less than segment number; Adjusting the segment number to 1
Sending 5, 100-byte MPLS Echos to 2.0.0.1,
     timeout is 2 seconds, send interval is 0 msec:

Codes: '!' - success, 'Q' - request not sent, '.' - timeout,
  'L' - labeled output interface, 'B' - unlabeled output interface,
  'D' - DS Map mismatch, 'F' - no FEC mapping, 'f' - FEC mismatch,
  'M' - malformed request, 'm' - unsupported tlvs, 'N' - no label entry,
  'P' - no rx intf label prot, 'p' - premature termination of LSP,
  'R' - transit router, 'I' - unknown upstream index,
  'X' - unknown return code, 'x' - return code 0

Type escape sequence to abort.
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 348/485/648 ms
R1#

!!!!!!!!!!!!!!!!!!!!! But SW1 and SW2 ports gets blocked
<<<<<<<<<<<<<<<<< Why is this happening ??????????????? <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

SW1#show spanning-tree vlan 99 bri | i BK
FastEthernet1/1      128.42   128    19 BKN     0 32768 c200.2e14.0001 128.42
SW1#

SW2# show spanning-tree vlan 100 bri | i BK
FastEthernet1/1      128.42   128    19 BKN     0 32768 c201.2e14.0002 128.42
SW2#

SW2#ping 99.0.0.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 99.0.0.1, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
SW2#

Setup on GNS3:
! SW2 too
SW1#show version | i IOS
Cisco IOS Software, 3700 Software (C3725-ADVENTERPRISEK9-M), Version 12.3(4)T4,  RELEASE SOFTWARE (fc2)
SW1#

! R2 too
R1#show version | i IOS
Cisco IOS Software, 7200 Software (C7200-ADVENTERPRISEK9-M), Version 12.2(33)SRE7, RELEASE SOFTWARE (fc1)
R1#

I have tried on real HW with same results

Comments

  • Hey,

    I'd put my money on a spanning-tree issue (haven't tested it) - what does "show spanning-tree blockedports" on SW1/SW2 tell you about the reason for the port being blocked?

    /Mark

  • Hi Mark,

    I think SW ports are getting blocked on both switches is because of inconsistent VLAN on the AC (e.i PE side interface to CEs)

    SW2#
    *Mar  1 00:16:43.735: %SPANTREE-2-RECV_PVID_ERR: Received BPDU with inconsistent peer vlan id 99 on FastEthernet1/1 VLAN100.
    *Mar  1 00:16:43.739: %SPANTREE-2-BLOCK_PVID_PEER: Blocking FastEthernet1/1 on VLAN99. Inconsistent peer vlan.
    *Mar  1 00:16:43.743: STP: VLAN99 sent Topology Change Notice on Fa1/1
    *Mar  1 00:16:43.799: STP: VLAN99 Fa1/1 -> blocking
    *Mar  1 00:16:43.799: STP: VLAN99 we are the spanning tree rootPVST+: restarted the forward delay timer for FastEthernet1/1

    *Mar  1 00:16:43.803: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking FastEthernet1/1 on VLAN100. Inconsistent local vlan.
    SW2#
    *Mar  1 00:16:43.839: STP: VLAN100 Fa1/1 -> blocking
    SW2#show spanning-tree blockedports

    Name                 Blocked Interfaces List
    -------------------- ------------------------------------
    VLAN99               Fa1/1
    VLAN100              Fa1/1

  • Hi,

    i ahd the same issue and found that interworking ip was the only one truly working. I did not look for a solution to this issue (without using interworking ip) too much but this can be a solution to this issue. 

     

    Hope this helps

    Alessio

  • Hi Alessio,

    THanks for looking. I actually went into a deep dive and found almost the same info... "interworking ip" is the key. I have documented the finding here for anyone who is interested... Also, i found that this happens only for IOS-XR.

    http://www.akbintel.com/mediawiki/index.php/MPLS/L2VPN/Tshoot/Switch_as_CE_Link_Flap_on_IOS-XR_Possible_Bug1

     

  • THanks for looking. I actually went into a deep dive and found almost the same info... "interworking ip" is the key. I have documented the finding here for anyone who is interested... Also, i found that this happens only for IOS-XR.

    If you're using XR or later XE with the EVC syntax you can easily switch between VLAN's by popping the outer tag in ingress before you do your xconnect. (assuming you do the same on both PE's)

    -v10d

     

  • True,

    But for CCIE SPv3 version (3.9.2 XR), you can do that am i right? So, in that case, we just have to use "interworking ipv4"

     

Sign In or Register to comment.