Re: 3650 COS/DSCP to queue mapping

sorry.. Joe.. just reloaded everything and I cannot use those switches now.

anyway.. nothing special:

pc1 side: cos3 + cos override.. as explained in the test
pc2 side: nothing.. no trust, no override.. nothing..

On Wed, Sep 5, 2012 at 5:25 AM, Joe Astorino <joeastorino1982_at_gmail.com>wrote:

> 99999,
>
> Can you post your configurations? I would like to see on both
> interfaces what you have configured for trust and other things.
>
> On Tue, Sep 4, 2012 at 1:46 PM, marc edwards <renorider_at_gmail.com> wrote:
> >
> http://www.cisco.com/en/US/docs/switches/lan/catalyst3750x_3560x/software/release/12.2_58_se/configuration/guide/swqos.html#wp1023954
> >
> >
> > Chart really says it all. What I find interested and (supporting your
> view)
> > is the fact that DSCP-to-CoS is never used....
> >
> > On Tue, Sep 4, 2012 at 9:04 AM, marc edwards <renorider_at_gmail.com>
> wrote:
> >
> >> So on those thoughts.... We need to trust dscp. trusting cos throughout
> >> will bypass switch from looking at dscp markings. trusting dscp will
> make
> >> switch look into packet to see dscp markings and use mappings to
> convert a
> >> cos value. This should hit the dscp-cos map and reference values from
> >> altered config.
> >>
> >> Marc
> >>
> >>
> >> On Tue, Sep 4, 2012 at 8:55 AM, marc edwards <renorider_at_gmail.com>
> wrote:
> >>
> >>> So... looks like you are tagging frames on PC NIC? Where is vlan 1
> vlan 2
> >>> config or are these PC's in same VLAN/subnet? Where is 'mls qos trust
> cos'
> >>> on fa 0/2?
> >>>
> >>> Marc
> >>>
> >>>
> >>> On Tue, Sep 4, 2012 at 8:46 AM, ccie99999 <ccie99999_at_gmail.com> wrote:
> >>>
> >>>> Command was like: MLS qos map dscp-cos 24 to 5
> >>>>
> >>>> Show mls QoS dscp-cos shows it's mapped correctly
> >>>> Il giorno 04/set/2012 17:35, "marc edwards" <renorider_at_gmail.com> ha
> >>>> scritto:
> >>>>
> >>>> > can you please provide command entered for dscp-cos map config?
> >>>> >
> >>>> > On Tue, Sep 4, 2012 at 8:31 AM, ccie99999 <ccie99999_at_gmail.com>
> wrote:
> >>>> >
> >>>> >> I did cos 3 + cos override on pc1 side and trust dscp on pc2 side.
> >>>> >> I can't do a show mls qos maps now but I set up a dscp24 to cos5
> >>>> mapping.
> >>>> >>
> >>>> >>
> >>>> >>
> >>>> >> On Tue, Sep 4, 2012 at 3:30 PM, marc edwards <renorider_at_gmail.com>
> >>>> wrote:
> >>>> >>
> >>>> >> > Can either of you do a sh mls qos maps? Also, please show access
> >>>> >> > interfaces config. My hunch is that the dscp-cos map hasn't been
> >>>> >> changed to
> >>>> >> > refelect dscp 24 as cos 05. I am also curious to see if you have
> >>>> trusted
> >>>> >> > cos or dscp on access. That will change things.
> >>>> >> >
> >>>> >> > Regards,
> >>>> >> >
> >>>> >> > Marc
> >>>> >> >
> >>>> >> >
> >>>> >> > On Tue, Sep 4, 2012 at 8:23 AM, ccie99999 <ccie99999_at_gmail.com>
> >>>> wrote:
> >>>> >> >
> >>>> >> >> I've labbed this (cos3->dscp24->cos5) and I see I receive cos3
> on
> >>>> the
> >>>> >> >> second pc as well as dscp24.
> >>>> >> >>
> >>>> >> >> pc1(vlan1) - sw - pc2(vlan2)
> >>>> >> >>
> >>>> >> >> (I do trust cos on pc2 interface side).
> >>>> >> >>
> >>>> >> >> I guess it's fine I see dscp24.. don't understand why I see
> cos3.
> >>>> >> >>
> >>>> >> >> thanks
> >>>> >> >>
> >>>> >> >>
> >>>> >> >> On Tue, Sep 4, 2012 at 12:33 PM, gp <gs4me2me_at_gmail.com> wrote:
> >>>> >> >>
> >>>> >> >> > Hi Joe,
> >>>> >> >> >
> >>>> >> >> > I tried lab what you wrote, and not have result that I
> expected.
> >>>> So I
> >>>> >> >> have
> >>>> >> >> > one question; in your opinion what cos value will have frame
> when
> >>>> >> leave
> >>>> >> >> > switch: cos 3 or cos 5?
> >>>> >> >> >
> >>>> >> >> > I had cos 3, that confuse me.
> >>>> >> >> >
> >>>> >> >> > Thanks
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > -----Original Message-----
> >>>> >> >> > From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On
> >>>> >> Behalf Of
> >>>> >> >> > Joe
> >>>> >> >> > Astorino
> >>>> >> >> > Sent: Thursday, August 30, 2012 6:34 PM
> >>>> >> >> > To: Anthony Sequeira
> >>>> >> >> > Cc: Matt Eason; Cisco certification
> >>>> >> >> > Subject: Re: 3650 COS/DSCP to queue mapping
> >>>> >> >> >
> >>>> >> >> > Hi Matt,
> >>>> >> >> >
> >>>> >> >> > Anthony answered your question simply and correctly, but I
> just
> >>>> >> wanted
> >>>> >> >> to
> >>>> >> >> > add some things that helped me understand this. Like Anthony
> >>>> said,
> >>>> >> >> > whatever
> >>>> >> >> > you trust is basically how the switch determines the queue at
> a
> >>>> high
> >>>> >> >> level,
> >>>> >> >> > but at a deeper level there are a few different mappings going
> >>>> on.
> >>>> >> >> Let's
> >>>> >> >> > assume you trust CoS. You would have:
> >>>> >> >> >
> >>>> >> >> > - CoS to DSCP mapping INTERNAL to the switch
> >>>> >> >> > - DSCP to CoS mapping INTERNAL to the switch
> >>>> >> >> > - CoS to output queue mapping
> >>>> >> >> >
> >>>> >> >> > The point I am making is that even though a frame comes in
> with a
> >>>> >> >> > particular
> >>>> >> >> > CoS value, that value COULD change internally based on the
> >>>> internal
> >>>> >> >> > COS-DSCP
> >>>> >> >> > and DSCP-COS, and the frame COULD be queued based on the value
> >>>> >> derived
> >>>> >> >> from
> >>>> >> >> > the internal mappings and not on the original value. Let's
> look
> >>>> at
> >>>> >> some
> >>>> >> >> > example output for a second
> >>>> >> >> >
> >>>> >> >> > Here are some mapping tables for cos-dscp, dscp-cos and
> >>>> cos-output-q
> >>>> >> on
> >>>> >> >> a
> >>>> >> >> > 3750 switch. Note these are probably not default values
> because
> >>>> this
> >>>> >> is
> >>>> >> >> a
> >>>> >> >> > production switch.
> >>>> >> >> >
> >>>> >> >> > Here is the COS to DSCP mapping:
> >>>> >> >> >
> >>>> >> >> > switch#sh mls qos maps cos-dscp
> >>>> >> >> > Cos-dscp map:
> >>>> >> >> > cos: 0 1 2 3 4 5 6 7
> >>>> >> >> > --------------------------------
> >>>> >> >> > dscp: 0 8 16 24 32 40 48 56
> >>>> >> >> >
> >>>> >> >> > Here is the DSCP to CoS mapping
> >>>> >> >> >
> >>>> >> >> > switch#sh mls qos map dscp-cos
> >>>> >> >> > Dscp-cos map:
> >>>> >> >> > d1 : d2 0 1 2 3 4 5 6 7 8 9
> >>>> >> >> > ---------------------------------------
> >>>> >> >> > 0 : 00 00 00 00 00 00 00 00 01 01
> >>>> >> >> > 1 : 01 01 01 01 01 01 02 02 02 02
> >>>> >> >> > 2 : 02 02 02 02 03 03 03 03 03 03
> >>>> >> >> > 3 : 03 03 04 04 04 04 04 04 04 04
> >>>> >> >> > 4 : 05 05 05 05 05 05 05 05 06 06
> >>>> >> >> > 5 : 06 06 06 06 06 06 07 07 07 07
> >>>> >> >> > 6 : 07 07 07 07
> >>>> >> >> >
> >>>> >> >> > Finally, here is the CoS to output queue mapping
> >>>> >> >> >
> >>>> >> >> > switch#sh mls qos map cos-output-q
> >>>> >> >> > Cos-outputq-threshold map:
> >>>> >> >> > cos: 0 1 2 3 4 5 6 7
> >>>> >> >> > ------------------------------------
> >>>> >> >> > queue-threshold: 2-1 2-1 3-1 3-1 4-1 1-1 4-1 4-1
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > Let's just look at CoS 3 for example. We see that CoS 3 is
> >>>> mapped to
> >>>> >> >> DSCP
> >>>> >> >> > 24. In turn DSCP 24 is mapped right back to CoS 3 in the DSCP
> >>>> to COS
> >>>> >> >> > mapping. In turn, CoS 3 is put into output queue 3,
> threshold 1.
> >>>> >> >> > Fine. So in this case, it comes in as CoS 3 and is queued
> based
> >>>> on
> >>>> >> CoS
> >>>> >> >> 3
> >>>> >> >> > because we trust CoS and because the DSCP-COS mapping is sort
> of
> >>>> >> >> "synced".
> >>>> >> >> > But...what if you went in and mucked with the DSCP-COS mapping
> >>>> >> >> internally
> >>>> >> >> > such that DSCP 24 was no longer mapped back to CoS 3? What if
> >>>> it was
> >>>> >> >> > re-mapped to CoS 5 ?
> >>>> >> >> >
> >>>> >> >> > So you COULD have the frame come in as CoS 3 ...internally we
> go
> >>>> CoS
> >>>> >> 3
> >>>> >> >> > --> DSCP 24, then DSCP 24 to CoS 5 then queued based on CoS 5
> >>>> >> >> >
> >>>> >> >> > These are intricate details, but when you are studying for the
> >>>> lab, I
> >>>> >> >> think
> >>>> >> >> > it is important to get to the dirty details! Best of luck
> and I
> >>>> hope
> >>>> >> >> this
> >>>> >> >> > helps you out.
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > On Thu, Aug 30, 2012 at 10:45 AM, Anthony Sequeira
> >>>> >> >> > <terry.francona_at_gmail.com> wrote:
> >>>> >> >> > > Hi Matt!
> >>>> >> >> > >
> >>>> >> >> > > What an AWESOME question. While the documentation does not
> >>>> make it
> >>>> >> >> > > clear, the value that you trust on ingress, in your example,
> >>>> CoS,
> >>>> >> is
> >>>> >> >> > > the marking that is used in the appropriate default queue
> >>>> mapping
> >>>> >> >> > > table on the egress port.
> >>>> >> >> > >
> >>>> >> >> > > Anthony Sequeira, CCIE, CCSI, VCP
> >>>> >> >> > > http://www.stormwind.com
> >>>> >> >> > > Twitter: @compsolv
> >>>> >> >> > > Facebook: http://www.facebook.com/compsolv
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > > On 8/29/12 9:11 PM, "Matt Eason" <matt.d.eason_at_gmail.com>
> >>>> wrote:
> >>>> >> >> > >
> >>>> >> >> > >>Hi Guys,
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>Can you help clarify the following. If I have a switchport
> >>>> >> configured
> >>>> >> >> > >>on a
> >>>> >> >> > >>3560 to trust CoS inbound, that cos value is then mapped to
> an
> >>>> >> >> > >>internal DSCP value via the COS>DSCP map. That s fine.
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>Does this switch then determine the output queue from the
> >>>> original
> >>>> >> CoS
> >>>> >> >> > >>value or the internal DSCP value which was assigned by the
> >>>> switch?
> >>>> >> I
> >>>> >> >> > >>see both a DSCP>Output queue map and a COS>Output queue map
> >>>> >> exists.
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>Thanks,
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>Matt
> >>>> >> >> > >>
> >>>> >> >> > >>
> >>>> >> >> > >>Blogs and organic groups at http://www.ccie.net
> >>>> >> >> > >>
> >>>> >> >> >
> >>>> >>
> >>>>
> >>______________________________________________________________________
> >>>> >> >> > >>_ Subscription information may be found at:
> >>>> >> >> > >>http://www.groupstudy.com/list/CCIELab.html
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > > Blogs and organic groups at http://www.ccie.net
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >>
> ______________________________________________________________________
> >>>> >> >> > > _ Subscription information may be found at:
> >>>> >> >> > > http://www.groupstudy.com/list/CCIELab.html
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> > >
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > --
> >>>> >> >> > Regards,
> >>>> >> >> >
> >>>> >> >> > Joe Astorino
> >>>> >> >> > CCIE #24347
> >>>> >> >> > http://astorinonetworks.com
> >>>> >> >> >
> >>>> >> >> > "He not busy being born is busy dying" - Dylan
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > Blogs and organic groups at http://www.ccie.net
> >>>> >> >> >
> >>>> >> >> >
> >>>> >>
> >>>>
> _______________________________________________________________________
> >>>> >> >> > Subscription information may be found at:
> >>>> >> >> > http://www.groupstudy.com/list/CCIELab.html
> >>>> >> >> >
> >>>> >> >> >
> >>>> >> >> > Blogs and organic groups at http://www.ccie.net
> >>>> >> >> >
> >>>> >> >> >
> >>>> >>
> >>>>
> _______________________________________________________________________
> >>>> >> >> > Subscription information may be found at:
> >>>> >> >> > http://www.groupstudy.com/list/CCIELab.html
> >>>> >> >>
> >>>> >> >>
> >>>> >> >> Blogs and organic groups at http://www.ccie.net
> >>>> >> >>
> >>>> >> >>
> >>>>
> _______________________________________________________________________
> >>>> >> >> Subscription information may be found at:
> >>>> >> >> http://www.groupstudy.com/list/CCIELab.html
> >>>> >>
> >>>> >>
> >>>> >> Blogs and organic groups at http://www.ccie.net
> >>>> >>
> >>>> >>
> >>>>
> _______________________________________________________________________
> >>>> >> Subscription information may be found at:
> >>>> >> http://www.groupstudy.com/list/CCIELab.html
> >>>>
> >>>>
> >>>> Blogs and organic groups at http://www.ccie.net
> >>>>
> >>>>
> _______________________________________________________________________
> >>>> Subscription information may be found at:
> >>>> http://www.groupstudy.com/list/CCIELab.html
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
> >
> >
> >
> >
> >
> >
> >
>
>
>
> --
> Regards,
>
> Joe Astorino
> CCIE #24347
> http://astorinonetworks.com
>
> "He not busy being born is busy dying" - Dylan

Blogs and organic groups at http://www.ccie.net
Received on Wed Sep 05 2012 - 05:36:19 ART