Is this right?

So you don't want:

[Phone1] -> DHCP(ef) -> [SWITCH1 (dscp-cos-map)] -> COS 5 -> [SWITCH2]
-> COS5 -> [SWITCH3 (cos-dscp-map 5->46 )] -> DSCP(ef) -> [Phone2]

You want DSCP end 2 end

[Phone1] -> DHCP(ef) -> [SWITCH1] -> DSCP(ef) -> [SWITCH2] -> DSCP(ef)
-> [SWITCH3] -> DSCP(ef) -> [Phone2]

/Ralph

2011/2/23 Jason Boyers <[email protected]>:
> SCCP will have both a source and destination TCP port of 2000 (please do
> verify this!)  If you do a sniffer capture, you will notice that RTP traffic
> between CME and a phone (like when using a wave file on CME with B-ACD) uses
> UDP port 2000 on the CME.  The phone side will be in the standard UDP
> 16384-32767 range.  So, for RTP traffic, the ACL should likely have two
> lines, one with a source port range of 16384-32767 and one with a
> destination port range of 16384-32767.
>
> When looking at QoS configurations for switchports, there are several things
> to keep in mind.  I'll address two here.  First, when you configure "mls
> qos," that automatically enables SRR or WRR on the ports with the default
> percentages and thresholds.  Additional configurations of SRR or WRR would
> be used to change the defaults.
>
> For the individual interface trust configurations, remember that if the port
> is an access port, there will not be any CoS markings in the frame to
> trust.  On a trunk port, you would generally trust CoS (if you need to trust
> anything.)  However, as mentioned, you normally want to trust DSCP on trunks
> between switches.  The reason is that the frames have already had their
> CoS-DSCP mappings on ingress to the switch.  Thus, they have an appropriate
> DSCP marking that you have already determined.  Let's say that you are
> trusting an end device's DSCP markings.  And, let's say that they send a
> packet with DSCP AF31.  On egress (with the default map,) that will be
> mapped to CoS 3.  On ingress, if you trust CoS, that will be remarked to
> DSCP CS3.  Thus, your trust of the end device marking is negated by trusting
> CoS on the trunk.
>
> Jason Boyers - CCIE #26024 (Wireless)
> Technical Instructor - IPexpert, Inc.
> Mailto: [email protected]
>
>
> On Wed, Feb 23, 2011 at 8:37 AM, Phil Priest <[email protected]> wrote:
>>
>> Hi,
>>
>>
>>
>> Looking into in further SCCP traffic would either have a source port of
>> 2000 or a destination port of 2000 depending on the direction of the flow.
>>  So I am thinking this below is correct. Would be good to get some
>> clarification on this as well as the other voice control ports…
>>
>>
>>
>> Phil
>>
>>
>>
>>
>>
>> ip access-list extended ACL-SCCP
>>  permit tcp any any eq 2000
>>  permit tco any eq 2000 any
>>
>>
>>
>>
>>
>> From: [email protected]
>> [mailto:[email protected]] On Behalf Of Stalder
>> Dominic
>> Sent: 23 February 2011 12:09
>> To: Leigh Jewell
>>
>> Cc: [email protected]
>> Subject: Re: [CCIE Wireless] "Exam Best Practices" - Port Configurations
>>
>>
>>
>> Hei Leigh
>>
>> Thanks for the detailed answers.
>>
>> > 1. Switches: I would configure 'mls qos trust dscp'. My thinking is here
>> > we 'mls qos trust cos' on trunks connected to WLC's.
>>
>> I thought than on trunk ports from switch to switch it would be good to
>> trust CoS? But I will check the link you send later on.
>>
>> > 2. WAN/Internet: You ACL for matching SCCP may not be correct. You are
>> > matching on src/dst of port 2000. From my information only the destination
>> > is 2000 and as such you ACL would need to look more like:
>>
>> I always used the ACL like you said:
>>
>> ip access-list extended ACL-SCCP
>>  permit tcp any any eq 2000
>>  permit tco any eq 2000 any
>>
>> But then I saw, that Jasons DSG Lab 2 has configured SRC 2000 <-> DST
>> 2000. I will internaly check this with our Voice guys.
>>
>> > I have a blog <http://leigh-cciewireless.blogspot.com/>  I am using as a
>> > study aid. Would you be ok if I add in the best practise example configs 
>> > you
>> > have built ? I think they will be a great reference and something to come
>> > back to at a later point to refresh.
>>
>> The mail has no copyright, so just add it, no problem ;-)
>>
>> Best regards
>> Dominic
>>
>> ________________________________
>>
>> Von: Leigh Jewell <[email protected]>
>> Datum: Wed, 23 Feb 2011 22:59:45 +1100
>> An: Dominic Stalder <[email protected]>
>> Cc: "[email protected]"
>> <[email protected]>
>> Betreff: Re: [CCIE Wireless] "Exam Best Practices" - Port Configurations
>>
>> This is exactly what I have been working on as well. Here are my thoughts:
>>
>> 1. Switches: I would configure 'mls qos trust dscp'. My thinking is here
>> we 'mls qos trust cos' on trunks connected to WLC's. The switch maps the cos
>> to a dscp and at that point through the network we trust dscp. This is
>> according to the QoS SRND
>> <http://www.cisco.com/univercd/cc/td/doc/solution/esm/qossrnd.pdf> .
>>
>> 2. WAN/Internet: You ACL for matching SCCP may not be correct. You are
>> matching on src/dst of port 2000. From my information only the destination
>> is 2000 and as such you ACL would need to look more like:
>>
>> ip access-list extended ACL-SCCP
>>  permit tcp any any eq 2000
>>  permit tco any eq 2000 any
>>
>> 3. CME - if the CME is marking the packets correctly I would put on the
>> switch port 'mls qos trust dscp' this will ensure the packets are not
>> written down to zero.
>>
>> 3. WiSM - you can't access the port-channels so you can't configure
>> 'spanning-tree portfast'
>>
>> 4. WLC (LAG) - the command should be 'mls qos trust cos'.
>>
>> 5. WLC (non-LAG): referring to the WLC best practise guide
>> <http://www.cisco.com/en/US/tech/tk722/tk809/technologies_tech_note09186a0080810880.shtml>
>> , STP is not recommended to be enabled.
>>
>> 6. WLC Service Port: The service port can't mark traffic. If you want to
>> mark it you will need to do a service input policy. I can't see a need to
>> mark it.
>>
>> 7. LAP (local) & LAP (HREAP): both of these look good;
>>
>> 8. Auton AP or IOS AP: The BVI interface on an AP is the management
>> interface and is always the native VLAN (untagged). From the AP perspective,
>> the untagged VLAN is VLAN 1.
>>
>> 9. Wired IP Phone: This one I have been struggling with. The fact they
>> would say not to use AutoQoS to me would suggest that they want SRR (for
>> 3560) or WRR (6500). Don't forget the hardware list means the phone could be
>> either on a 3560/2960 or 6500. Then there are the different modules in the
>> 6500 which have different queues and as such different QoS configurations. I
>> need to work on this one some more.
>>
>> 10. Portfast & BPDU guard: If they use the wording something like 'fast
>> and secure' - fast would imply port-fast while secure would be the bpdu
>> guard feature.
>>
>> 11. Priority Queue out: any port that would carry voice traffic would be
>> good to put this on. Even if you did it for other ports that didn't carry
>> voice it would have no determental affect I can think of.
>>
>> I have a blog <http://leigh-cciewireless.blogspot.com/>  I am using as a
>> study aid. Would you be ok if I add in the best practise example configs you
>> have built ? I think they will be a great reference and something to come
>> back to at a later point to refresh.
>>
>> Cheers,
>> Leigh
>>
>>
>> On 20 February 2011 02:13, Stalder Dominic <[email protected]>
>> wrote:
>>
>> Hi there
>>
>> I have been once at the lab exam and I think, there are tasks in the
>> infrastructure section, that will be the same in EVERY lab exam, so I
>> thought that we can start here some “exam best practices” conversations, so
>> we can get these points for sure ;-) If someone is interested, just take
>> part and help others to pass the exam. I would like to start with default
>> port configurations:
>>
>> - Trunking vs. Access
>> - Spanning Tree portfast and bpduguard
>> - QoS
>> - etc.
>>
>> I know there can be variations in the questions, but as a general
>> guideline and as a discussion base. But anyway, these are my proposals (some
>> of the information I took out of the DSG from Jason!) for the different port
>> types (by the way, sorry for the strange format, but I copied this out of my
>> Wiki post, I hope you can read anyway):
>>
>>
>> --- Switches ---
>>
>> <configuration start>
>> port-channel load-balance src-dst-ip
>> !
>> mls qos
>> mls qos map cos-dscp 0 8 16 24 32 46 48 54
>> mls qos map dscp-cos 46 to 5
>> mls qos map dscp-cos 24 to 3
>> !
>> interface fastethernet x/x
>>  switchport trunk encapsulation dot1q
>>  switchport mode trunk
>>  switchport trunk native vlan x (if specified by the question)
>>  switchport trunk allowed vlan x,y,z
>>  priority-queue out
>>  mls qos trust cos
>> !
>> <configuration end>
>>
>>
>>
>> --- WAN / Internet ---
>>
>> <configuration start>
>> ip access-list extended ACL-RTP
>>  permit udp any range 16384 32767 any range 16384 32767
>> !
>> ip access-list extended ACL-SCCP
>>  permit tcp any eq 2000 any eq 2000
>>  permit tcp any eq 2002 any eq 2002
>> !
>> class-map MAP-RTP
>>  match access-group name ACL-RTP
>> !
>> class-map MAP-SCCP
>>  match access-group name ACL-SCCP
>> !
>> policy-map POLICY-VOICE
>>  class MAP-RTP
>>   set dscp ef
>>  class MAP-SCCP
>>   set dscp cs3
>> !
>> interface fastethernet x/x
>>  no switchport
>>  ip address x.x.x.x y.y.y.y
>>  service-policy POLICY-VOICE in
>>  priority-queue out
>> !
>> <configuration end>
>>
>>
>>
>> --- CME ---
>> *If the question says, the CME already tags the packets with the right QoS
>> marking, what do we have to configure on the port concerning QoS?
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport mode access
>>  switchport access vlan x
>>  spanning-tree portfast
>>  spanning-tree bpduguard enable
>>  priority-queue out
>> <configuration end>
>>
>>
>>
>> --- WiSM ---
>> *For the WiSM I would use the '''wism'''  commands, but is it possible /
>> necessary to add the '''spanning-tree portfast trunk'''  or '''spanning-tree
>> bpduguard'''  commands (actually I don't have access to a 650x with WiSM
>> module)?
>>
>> <configuration start>
>> wism service-vlan z
>> !
>> wism module x controller 1 native-vlan x (if management is not tagged)
>> wism module x controller 1 allowed-vlan y,z
>> wism module x controller 1 qos-trust cos
>> !
>> wism module x controller 2 native-vlan x (if management is not tagged)
>> wism module x controller 2 allowed-vlan y,z
>> wism module x controller 2 qos-trust cos
>> <configuration end>
>>
>>
>>
>> --- WLC (LAG) ---
>>
>> <configuration start>
>> interface fastethernet x/x
>>  channel-group 1 mode on
>> !
>> interface port-channel 1
>>  switchport trunk encapsulation dot1q
>>  switchport mode trunk
>>  switchport trunk native vlan x (if specified by the question)
>>  switchport trunk allowed vlan x,y,z
>>  spanning-tree portfast trunk
>>  spanning-tree bpduguard enable
>>  priority-queue out
>>  mls qos cos
>> !
>> <configuration end>
>>
>>
>>
>> --- WLC (Connected to different switches, for example 4402 with 2 ports
>> connected to both core switches) ---
>> *I do not add '''spanning-tree bpduguard enable'''  because I assume that
>> on the WLC the STP is enabled
>> *General question, I think it is necessary to enable the STP on WLCs that
>> are connected to different switches, isn't it?
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport trunk encapsulation dot1q
>>  switchport mode trunk
>>  switchport trunk native vlan x (if specified by the question)
>>  switchport trunk allowed vlan x,y,z
>>  priority-queue out
>>  mls qos cos
>> !
>> <configuration end>
>>
>>
>>
>> --- WLC (Service Port) ---
>> *Are here any QoS commands needed, and if so, what will be trusted?
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport mode access
>>  switchport access vlan x
>>  spanning-tree portfast
>>  spanning-tree bpduguard enable
>> !
>> <configuration end>
>>
>>
>>
>> --- LAP (Local) ---
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport mode access
>>  switchport access vlan x (always needed for management interface)
>>  spanning-tree portfast
>>  spanning-tree bpduguard enable
>>  priority-queue out
>>  mls qos trust dscp
>> !
>> <configuration end>
>>
>>
>>
>> --- LAP (H-REAP) ---
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport trunk encapsulation dot1q
>>  switchport mode trunk
>>  switchport trunk native vlan x (always needed for management interface)
>>  switchport trunk allowed vlan x,y,z
>>  priority-queue out
>>  mls qos cos
>> !
>> <configuration end>
>>
>>
>>
>> --- AAP (Multiple VLANs) ---
>> *The management interface does not always have to be the native VLAN, does
>> it?
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport trunk encapsulation dot1q
>>  switchport mode trunk
>>  switchport trunk native vlan x (if specified by the question)
>>  switchport trunk allowed vlan x,y,z
>>  spanning-tree portfast trunk
>>  spanning-tree bpduguard enable
>>  priority-queue out
>>  mls qos cos
>> !
>> <configuration end>
>>
>>
>>
>> --- AAP (Single VLAN, for example if used for a WGB bridge and only one
>> VLAN is transported) ---
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport mode access
>>  switchport access vlan x
>>  spanning-tree portfast
>>  spanning-tree bpduguard enable
>>  priority-queue out
>>  mls qos dscp
>> !
>> <configuration end>
>>
>>
>>
>> --- Wired IP Phone---
>> *The questions says, you have to configure a port for future use of an
>> wired IP phone?
>> *You must not use Auto-QoS, this would give us something like this:
>>
>> <configuration start>
>> interface fastethernet x/x
>>  srr-queue bandwidth share 10 10 60 20
>>  priority-queue out
>>  mls qos trust device cisco-phone
>>  mls qos trust cos
>>  auto qos voip cisco-phone
>>  service-policy input AutoQoS-Police-CiscoPhone
>> <configuration end>
>>
>> *I don' think, that srr-queue and service-policy configuration is expected
>> in the CCIE Wireless track for a wired IP phone port (what do people say,
>> that already passed?)
>> *So I think this configuration could give the points we want (I add
>> '''spanning-tree bpduguard enable'''  because the IP phone will not send any
>> BPDUs):
>>
>> <configuration start>
>> interface fastethernet x/x
>>  switchport mode access
>>  switchport access vlan x
>>  switchport voice vlan y
>>  spanning-tree portfast
>>  spanning-tree bpduguard enable
>>  priority-queue out
>>  mls qos trust device cisco-phone
>>  mls qos trust cos
>> !
>> <configuration end>
>>
>>
>>
>> And here are some general questions, I would like to know more about:
>> *Would it be OK to add ''priority-queue out'' on every port?
>> *On which ports would you use '''spanning-tree portfast'''  and
>> '''spanning-tree bpduguard enable'''?
>>
>> So I hope this can be used as a discussion base and I hope I get some
>> interesting reactions on this ;-) Please feel free to criticize it.
>>
>> Regards
>> Dominic
>>
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please
>> visit www.ipexpert.com <http://www.ipexpert.com/>
>>
>>
>>
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please
>> visit www.ipexpert.com
>>
>
>
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please
> visit www.ipexpert.com
>
>
_______________________________________________
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