[c-nsp] TTL not decrementing (MPLS, SXI, Sup720)

[Tim Durack]

On Wed, Mar 9, 2011 at 3:28 PM, Phil Mayers <p.mayers at imperial.ac.uk> wrote:

> On 03/09/2011 08:20 PM, Tim Durack wrote:
>
>  I think I'm seeing something similar with a few
>> 6504/SUP720-3BXL/6724-CFC running 12.2(33)SXI3.
>>
>> Traceroutes crossing these units in the global table timeout. Works fine
>> in a VRF.
>>
>
> Timeout at which hop? Can you give an example?


Correction: traceroute originating/terminating at one of these units fail:

SUP720-3BXL-6724-RTR-1#traceroute mpls ipv4 SUP720-3BXL-6724-RTR-2
Tracing MPLS Label Switched Path to SUP720-3BXL-6724-RTR-2, timeout is 2
seconds

<snip>

Type escape sequence to abort.
  0 10.241.1.1 MRU 9216 [Labels: implicit-null Exp: 0]
. 1 *
. 2 *

SUP720-3B-6748-RTR-1#traceroute mpls ipv4 SUP720-3B-6748-RTR-2
Tracing MPLS Label Switched Path to SUP720-3B-6748-RTR-2, timeout is 2
seconds

<snip>

Type escape sequence to abort.
  0 10.247.1.1 MRU 9216 [Labels: implicit-null Exp: 0]
! 1 10.247.1.2 1 ms


VS-S720-6748-RTR-1#traceroute mpls ipv4 VS-S720-6748-RTR-2
Tracing MPLS Label Switched Path to VS-S720-6748-RTR-2, timeout is 2 seconds

<snip>

Type escape sequence to abort.
  0 10.1.1.1 MRU 9216 [Labels: implicit-null Exp: 0]
! 1 10.1.1.2 1 ms

Tracerouting across works fine.

So 3BXL+6724 !good, 3B+6748 is good, 3C+6748 good.


>> I did read some docs about this at one point; but I've not been able to
> find them again since. I suspect it was in relation to the PFC-3C, so you
> might try hunting for the docs on that.
>
> Or it might have been during one of my "read all the TAC bugs in the
> release notes" sessions - perhaps try that.
>
> Or open a TAC?
>
>
Yup, I'll give that a shot. I usually find cisco-nsp more helpful ;-|


> To emphasise my earlier point: after I read whatever I read, I came away
> pretty sure this is a hardware bug in the PFC-3B, and there's nothing that
> can be done to fix it.
>
> I'll see if I can find the docs again.
>

Thanks for the input.

-- 
Tim:>