EoMPLS vlan rewrite between brands; possibly new bug in Cisco IOS 15

Jonas Bjork mr.jonas.bjork at me.com
Sun Nov 15 02:02:00 UTC 2015

Thank you Jeff, I'll check it out on the HP side since Cisco seems to not care:

Known Fixed Releases:	(0)
No release planned to fix this bug

Best regards,
Jonas Bjork

> On 15 Nov 2015, at 2:54, Jeff Tantsura <jeff.tantsura at ericsson.com> wrote:
> Jonas,
> As expected - the problem is related to vc type negotiation.
> You have hit CSCuq28998 :)
> talk to your cisco rep	
> Workaround:
> - configure VC type 5 between the routers (configured on HP side)
> - configuring no-control-word 
> The bug has been reported in 15.2(4)S4a, perhaps there’s an image with the problem fixed.
> Cheers,
> Jeff
> On 11/14/15, 17:31, "Jonas Bjork" <mr.jonas.bjork at me.com> wrote:
>> Dear Mr. Jeff,
>> Thank you for your reply. Below is the complete output in question (l2 is short for l2transport).
>> You are mentioning platform capabilities and that the default might have changed. How do I alter this?
>> pe#sh mpls l2 vc 42 d
>> Local interface: Po190.42 up, line protocol up, Eth VLAN 42 up
>> Destination address: X.X.1.89, VC ID: 42, VC status: down
>>   Last error: Imposition VLAN rewrite capability mismatch with peer
>>   Output interface: none, imposed label stack {}
>>   Preferred path: not configured
>>   Default path: no route
>>   No adjacency
>> Create time: 00:00:59, last status change time: 00:31:40
>>   Last label FSM state change time: 00:00:18
>>   Last peer autosense occurred at: 00:00:18
>> Signaling protocol: LDP, peer X.X.1.89:0 up
>>   Targeted Hello: X.X.0.2(LDP Id) -> X.X.1.89, LDP is UP
>>   Graceful restart: not configured and not enabled
>>   Non stop routing: not configured and not enabled
>>   Status TLV support (local/remote)   : enabled/not supported
>>     LDP route watch                   : enabled
>>     Label/status state machine        : remote invalid, LruRnd
>>     Last local dataplane   status rcvd: No fault
>>     Last BFD dataplane     status rcvd: Not sent
>>     Last BFD peer monitor  status rcvd: No fault
>>     Last local AC  circuit status rcvd: No fault
>>     Last local AC  circuit status sent: DOWN PW(rx/tx faults)
>>     Last local PW i/f circ status rcvd: No fault
>>     Last local LDP TLV     status sent: No fault
>>     Last remote LDP TLV    status rcvd: Not sent
>>     Last remote LDP ADJ    status rcvd: No fault
>>   MPLS VC labels: local 242, remote 1199
>>   Group ID: local 0, remote 0
>>   MTU: local 9216, remote 9216
>>   Remote interface description:
>>   Remote VLAN id: 42
>> Sequencing: receive disabled, send disabled
>> Control Word: Off (configured: autosense)
>> SSO Descriptor: X.X.1.89/42, local label: 242
>> Dataplane:
>>   SSM segment/switch IDs: 0/0 (used), PWID: 142
>> VC statistics:
>>   transit packet totals: receive 0, send 0
>>   transit byte totals:   receive 0, send 0
>>   transit packet drops:  receive 0, seq error 0, send 0
>> pe#
>> Anyone else: feel free to join in. Maybe we have any L2VC/PW ninjas watching.
>> Best regards,
>> Jonas Bjork
>>> On 15 Nov 2015, at 1:26, Jeff Tantsura <jeff.tantsura at ericsson.com> wrote:
>>> Been forever since i looked at cisco, however sounds like vc type mismatch. They used to have it as a platform capability, perhaps SW upgrade changed the default.
>>> to my memory "show mpls l2 transport" should provide enough details.
>>> Hope this helps
>>> Regards,
>>> Jeff
>>>> On Nov 14, 2015, at 4:50 AM, Jonas Bjork <mr.jonas.bjork at me.com> wrote:
>>>> Hi, I am using a couple of AToM/EoMPLS tunnels in order to carry customer voice and data traffic across our IP/MPLS core, and it is currently working just fine. The first side consists of a Cisco 7600 router (rsp) and the other one is an HP A5500-HI routing switch with full LER/E-LSR capability. At the HP site, the tunnels are facing the access ports towards our premium end-customers; and on the Cisco PE I terminate the tunnels on one of the 2x10GE portchannel backbone links. There is vlan X on the HP side and vlan Y on the Cisco side - vlan rewrite is working perfectly - as long as I use IOS 12.
>>>> After upgrading the Cisco router software to IOS 15 the tunnels won't come up. sh mpls l2 vc Y d says:
>>>> ...
>>>> Last error: Imposition VLAN rewrite capability mismatch with peer
>>>> ...
>>>> I use almost exactly the same Cisco configuration before and after the upgrade (only minor changes and nothing related to this) and I havn't touched the HP. Apparently they don't talk the same L2PW language. I wonder though, why now? We use service instances on the HP switchport as endpoint, we initiate the targetted LDP session in addition to the pseudowire handshake from a sub interface MPLS crossconnect. There is no MTU mismatch; not here - not anywhere.
>>>> Anyone heard of this issue or experienced it?
>>>> Best regards,
>>>> Jonas Björk
>>>> SNE, Europe/Sweden (hope you guys will help me anyway:)

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