Re: cos rewriting on switch

Jack,

I specified in my previous email that you have to mark your service class 184
on your ping tests.B I meant TOS (type of service) not to be confused with
dscp values.

TOS values:

binary 101110, the full TOS value is 101111000 which is decimal 184, or in hex
0xB8.B

- Mark
----- Original Message -----
From: mwcombs_at_comcast.net
To: "Jack Router" <pan.router_at_gmail.com>
Cc: ccielab_at_groupstudy.com
Sent: Wednesday, November 10, 2010 9:30:45 AM
Subject: Re: cos rewriting on switch

Jack,

Your traffic leaving R2 must mark it's traffic with cos5 or 0x2e in hex which
equates to an precedence 5.B B Is your router2 even marking your traffic
properly?B B I would setup a monitoring port on port 2 which connects to
router
2 to validate the packets coming in are indeed marked properly.B B My guess
they are not.

Another thought is why are you trying to look for a greated cos value then 0
on an ICMP packet?B B When you do your pings are you using extended options
commands and specifing service class 184?B B You will need to do this if you
want to mark your packet with cos vaule of 5.B B If not your pings will just
be
normal pings.

- Mark Combs

----- Original Message -----
From: "Jack Router" <pan.router_at_gmail.com>
To: ccielab_at_groupstudy.com
Sent: Tuesday, November 9, 2010 10:31:18 PM
Subject: cos rewriting on switch

Hello all,

I have a question about cos rewriting on a switch. Here is scenario:

R1(f0/0.100)-----dot1q------(f0/1)SW1(f0/2)------access-------(f0/0)R2

On R1 I configured class maps and policy map to identify what cos is
received.
SW1 has NO mls qos enabled or any cos configuration.

When I ping R1 from R2 i see that R1 receives packets marked with cos0. Why
? Packets that leave R2 are not tagged with cos value, why then R1 receives
packets cos0 ?
Is cos0 a synonym of no cos marking ?

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Received on Wed Nov 10 2010 - 15:50:24 ART