11 May

Creating EoMPLS on ASR9k

Process of defining E-Line connections, either local or as EoMPLS, consists of two steps – creation of EFP’s (Ethernet Flow Point) and defining xconnect between them. Each EFP represents one customer service demarcation point and can be in example physical subinterface or bundle. Connection between EFP’s can be either local, if both ESP’s are in the same chassis (same or different line cards) or EoMPLS link.

Creation of EFP is simple, you just have to define subinterface as l2transport to let it be assigned into xconnent int l2vpn service

interface GigabitEthernet0/2/0/24.1 l2transport
 encapsulation dot1q 61

On each EFP many operations can be performed such as VLAN’s popping, pushing or rewriting. Only first two levels of VLAN tagging are supported and 802.1ad and 802.1q tags are supported as an outer tags, and only 802.1q as inner tag.

Now when EFP’s are defined we can create xconnect between them. If E-Line is local the xconnect would consist of two interfaces

l2vpn
 xconnect group AC2AC_6
  p2p LOCAL_ELINE
   interface Bundle-Ether600.1
   interface Bundle-Ether601.1

In this example L2 Etherchannel interfaces were used. Under each xconnect group more than one p2p connects can be defined. This let you keep configuration logically separated.

Creation of EoMPLS connects is similar, just one end of it is local EFP, and second one is other router within MPLS cloud. Also backup pseudo-wire can be defined to protect against network breakdowns

l2vpn
 xconnect group AC2PW_6
  p2p PE6_PE4_6_A
   interface Bundle-Ether600.2
   neighbor 10.4.4.4 pw-id 601
    backup neighbor 10.5.5.5 pw-id 601

Verification can be done using show l2vpn xconnect command

RP/0/RSP0/CPU0:PE6#show l2vpn xconnect 
Legend: ST = State, UP = Up, DN = Down, AD = Admin Down, UR = Unresolved,
        LU = Local Up, RU = Remote Up, CO = Connected, SB = Standby

XConnect                   Segment 1                   Segment 2                
Group      Name       ST   Description            ST   Description            ST
------------------------   -------------------------   -------------------------
AC2AC_6    LOCAL_ELINE
                      UP   BE600.1                UP   BE601.1                UP

--------------------------------------------------------------------------------
AC2PW_6    PE6_PE4_6_A
                      UP   BE600.2                UP   10.4.4.4        601    UP
                                                       Backup                   
                                                       10.5.5.5        601    DN
--------------------------------------------------------------------------------

As we can see xconnects are up, except of backup pseudo-wire that will goes up only when primary one goes down.

5 thoughts on “Creating EoMPLS on ASR9k

  1. Have you had any experience mesuring EoMPLS going over two routers with a similar setup as your post? I setup a EoMPLS to carry two vlans. the vlans are on their own PW.

    the odd part is I am getting 3ms ping responses back and forth over the pseudowire running over two ASR9000s. is this normal?

    • I never looked deep down on RTT over EoMPLS PW’s. The main question is how long is the distance between routers and if you’re having same delay while transporting native dot1q over routers. I don’t have access to ASR9k now to check it.

  2. I am having tough time with one end having a 7600 ios based router with xconnect command on the SVIs and the other end is ASR9001 with the above l2transport options. The VCs come up but cant seem to pass any traffic.

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