Hi Steve, Thanks for that, yes it does appear to be all untagged (and non-IP) frames which get assigned ‘unwanted’ EXP values. This seems to occur despite the trust/untrust/mutate state of the xconnect interface.
There is no control over the downstream traffic, the xconnect is to encapsulate and carry EoMPLS to a remote location but the EXP should be statically set for all frames in order to comply with the core QoS policies. Any further ideas beyond that? A similar setup on our own 9k platform works as expected, so this appears to be a specific 6500 feature. All the best, Robert Williams Custodian Data Centres https://www.CustodianDC.com From: Steve Dodd [mailto:sd...@salesforce.com] Sent: 09 February 2018 16:02 To: Robert Williams <rob...@custodiandc.com> Cc: cisco-nsp@puck.nether.net Subject: Re: [c-nsp] MPLS EXP on STP Frames (6500) IIRC the EXP values for non-IP traffic are mapped directly from the .1p COS values. Depending on your flavor of STP this field may not even exist, in which case I suspect it is being treated as COS0. Is it possible to have the downstream device push a .1q tag? Cheers, Steve On Fri, Feb 9, 2018 at 8:41 AM, Robert Williams <rob...@custodiandc.com<mailto:rob...@custodiandc.com>> wrote: Hi all, Is anyone aware of a feature which allows the EXP value on an STP frame to be set when it is encapsulated by a xconnect on a 6500? Example config: int gi1/1 description Customer Port xconnect 1.2.3.4 666 encapsulation mpls service-policy input set-exp-3 policy-map set-exp-3 class class-default set mpls experimental imposition 3 I would expect all traffic which ingresses on that customer port to be set to EXP 3 when it is encapsulated. This is, unfortunately, not the case.... When the traffic egresses the 6500, it is 'mostly' set to EXP 3 - except - a few special things, like the STP frames, LLDP and some other control-type stuff. Basically, only the IP stuff gets set to EXP 3. Control things get various values, STP for example goes to EXP 0 - and nothing changes this as far as I can find. I have also noticed some other types of traffic are set to other values (like EXP 5,6,7) so clearly there are more exceptions than just STP, but I figure that they are probably controlled by the same knob/feature, somewhere... Platform is Cat6500 with S720-10G, X6748 cards and IOS 15.1(2)SY6 It's a specific customer requirement so changing platform isn't an option in this case. I've also tried re-writing it (to EXP 3) on egress out of the box towards the MPLS core, but this isn't supported on this platform. I also tried setting it on the tunnel, but again that is only supported in ingress, not egress... So - any ideas anyone? Cheers! Robert Williams Custodian Data Centres https://www.CustodianDC.com _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net<mailto:cisco-nsp@puck.nether.net> https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list cisco-nsp@puck.nether.net https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
