"mls qos trust dscp" vs. "mls qos trust cos"

Are these statements correct ?
1. If using QoS profile without setting "wired qos protocol", always use "mls qos trust dscp" on the WLC trunk port
- downstream wmm traffic will be policed down to "?" (this one I'm not sure, is it "not policed" or "policed down to cos 6 for platinum, etc")
Ans: Not sure about always. you can use both 'mls qos trust dscp' and 'mls qos trust cos'. Since it is a trunk port the packets will have a cos value (802.1p tag) and hence you can trust cos. Downstream and upstream traffic both are capped to the WLAN max QoS value. for example if Wlan is set to silver, and if a packet comes in at platinum QoS, the AP will cap it to silver in upstream direction. Same holds true for a cos 5 / dscp 46 packet coming in from the wired side.
2. If using QoS profile with setting "wired qos protocol",
- use "mls qos trust cos" on the WLC trunk port if you want outgoing LWAPP traffic COS/DSCP to reflect QoS profile setting and if you want to rewrite DSCP in the outgoing upstream traffic to QoS profile setting
- use "mls qos trust dscp" on the WLC trunk port if you want LWAPP traffic COS/DSCP to reflect original DSCP setting and if you want to leave DSCP alone in the outgoing upstream traffic
Ans:
3. With either "mls qos trust cos" or "mls qos trust dscp" on WLC trunk port, downstream wmm traffic will be policed down to "wired qos protocol" setting (What if "wired qos protocol" is not set, will it be policed down to, for example, cos 6 for Platinum?)
Ans: Traffic in both direction wil always get capped to WLAN max QoS. Untagged (802.1p = 0) traffic will be treated as best effort.
4. Always use "mls qos trust dscp" on non-HREAP AP ports
Use "mls qos trust dscp" on HREAP AP ports, if you want to preserve upstream DSCP for locally switched WLANs
Use "mls qos trust cos" on HREAP AP ports, if you want to QoS profile 802.1p to override upstream DSCP for locally switched WLANs
Ans:
5. Use either "mls qos trust dscp" or "mls qos trust cos" on switch-to-switch trunks
Ans: I think on purely layer 2 switches you can trust dscp, but am not 100% sure.

Similar Messages

Cisco 3560 switch| mls qos trust dscp question

Hi everybody
Hi everybody .
Please consider the following example:
3560 sw f1/1--------trunk---SW2
3560 sw
f1/1
mls qos trust dscp
3560 is using default cos-dscp map, assume a 3560 receives a frame carrying IP packet on f1/1 with COS 4, what will 3560 switch do?
1) will it use its default cos --dscp map ( cos 4--.dscp 32) and rewrite 32 in dscp field of the packet in the frame and provide PHB for dscp 32 ?
Much appreciated!!
Have a great weekend.

Hi
No it will not trust the cos value, because You have configured to trust dcsp. So, the switch will trust the dcsp value in the incoming frame.
/Mikael

MQC QoS - C3650 - DSCP Trust

Hi,
We are migrating from 3750's to 3650's and I need to move the QoS over. In my policy map I would normally trust DSCP, but on the 3650's, there doesnt seem to be a trust DSCP command. Below is my policy map config:
policy-map vvc-map
class voice
trust dscp
class video
trust dscp
class control
trust dscp
class control-VoIP
trust dscp
Does anyone have any ideas on what has replaced the trust DSCP command in the policy map or is there a different way of doing it now?
Thanks,
Mark

Hi Mark
In IOS XE (3650/3850) no trust dscp option on policy map config.
Here is a doc on how trust works on those switches.
http://www.cisco.com/en/US/docs/solutions/Enterprise/Video/qoscampuscat3x50aag.html#wp1052949
HTH
Regards
Carlo

Why does mls qos trust dscp dissapear after reboot?

The command takes but after reboot, Invlaid inputs detected show up and "mls qos tust dscp" is gone from every interface.
Happens on both 2960-24PC-S / 2960-48PST-S switches.

Hi,
thanks for your reply.
mls qos
interface GigabitEthernet3/34
description *** DATA VLAN 35 - VOICE VLAN 34 ***
switchport
switchport trunk native vlan 36
switchport trunk allowed vlan 34,36
switchport mode trunk
mls qos trust dscp
no cdp enable
spanning-tree portfast trunk
If i don't include the global 'mls qos' command then the voice packets keep the dscp 46 value. If I add the mls qos command this causes the switch to set the dscp values to zero.
Thanks again
ps. there are some other mls commands on the switch... i don't know if these could interfere but they were already on there so i'm reluctant to remove them..

Mls qos trust dscp??? is setting my DSCP values to zero!?

Hi,
I was just doing some testing to ensure that the command 'mls qos trust dscp' is working on my 6509 switches before rolling out QoS.
Before adding any configuration I could see using wireshark that traffic from my Avaya 9608 handset was coming through with a DSCP value of 46 (as it is supposed to).
I then added the command 'mls qos' (at global level)
on examining the wireshark output this time, the DSCP value had been set to zero (i.e. it defaulted it to best effort)
I then expected by adding the commmand 'mls qos trust dscp' on the interface the phone is connected to that the DSCP value would would again be left alone?
does anybody know why this is happening?
Many thanks in advance.
Andy

Hi,
thanks for your reply.
mls qos
interface GigabitEthernet3/34
description *** DATA VLAN 35 - VOICE VLAN 34 ***
switchport
switchport trunk native vlan 36
switchport trunk allowed vlan 34,36
switchport mode trunk
mls qos trust dscp
no cdp enable
spanning-tree portfast trunk
If i don't include the global 'mls qos' command then the voice packets keep the dscp 46 value. If I add the mls qos command this causes the switch to set the dscp values to zero.
Thanks again
ps. there are some other mls commands on the switch... i don't know if these could interfere but they were already on there so i'm reluctant to remove them..

Qos trust cos or qos trust dscp?

My core switches are a pair Cisco catalyst 4006s with a sup 4 module. The questions are:
1. Should I use qos trust cos or qos trust dscp when setting up qos on a per port basis?
2. Which is preferred?
3. I have a cos to dscp mapping so does it really matter?
Any help is greatly appreciated. I just want to make sure that I'm honoring all tags.
Mark

If you have ip phones connected to the switch, you can enter qos trust cos on the switch and in the router which is connected to the switch enter the command to trust the DSCP since the switch will pass the dscp information to teh router.
http://www.cisco.com/en/US/docs/ios/qos/command/reference/qos_m2.html#wp1015945

QoS trust dscp or cos on catalyst 4500

We have a 4510R with Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software cat4500e-UNIVERSALK9-M), Version 03.05.02.E RELEASE SOFTWARE (fc1).
I want use qos trust dscp or qos trust cos on the interface conected to other cisco switch or wlan controller.
The current IOS version, do not support qos trust dscp:
SW(config)#interface gi10/16
SW(config-if)#qos tr
SW(config-if)#qos trust ?
device trusted device class
extend Extend trust through a connected device
SW(config-if)#qos trust device ?
cisco-phone   Cisco IP Phone
cts           Cisco-telepresence
ip-camera     Cisco video surveillance camera
media-player Cisco Digital Media Player
SW(config-if)#qos trust device
What is the software that I need for this?. I tried with command lookup tool but the cat4500 do not appears.

That is even new for me.
I did a search and found that, now a days you no longer have to provide the Trust DSCP command, it is by default trusted.
Went through this White Paper and excerpts are below:
http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-4500-series-switches/white_paper_c11-539588.html
The answer to your question comes from the following excerpt :-
"Previously supervisor engines relied on “port trust” to classify traffic; however, this does not fall into the MQC CLI construct. MQC provides a more flexible capability, i.e. all traffic is trusted by default, an administrator can change this trust state using a policy map. Another difference is the “internal DSCP” value used within the switch to place packets in the proper queue.
Cisco Catalyst 4500E Supervisor Engines do not use “internal DSCP”; rather, it relies on explicit matching of QoS values using class maps so that packets can be placed in the correct queue.
Also, note that there is no specific priority queue: it is not queue 3 or queue 1. The priority queue is simply configured within a class; therefore, it is not tied to a specific queue. One final difference is that of classification. Cisco Catalyst 4500E Supervisor Engines provide sequential classification rather than parallel. This allows the network administrator to classify traffic at egress based on the ingress markings. These markings can be done unconditionally, using a policer or using a table map. Based on these changes, QoS CLI will now be more contiguous on the Supervisor Engines as it will now have standard Cisco MQC CLI, making configuration management much simpler"
HTH,
Please rate all helpful posts.
Regards

Question about 3750 mls qos map dscp-output-q and cos-output-q

1. If a egress packet has both Cos and Dscp setting, which map should this packet used to put into queue?
2. The 3750 is doing ip route. After the packet is routed, will the packet keep the DSCP and COS? Or it will just keep the DSCP and using the dscp-cos map to create a new COS.

Apologies for the confusion with the terminalogy.
The question is where you have configured the trust boundaries, do you necessarily trust the DSCP value prior to being routed across your network?
Therefore, although you have explicity trusted the DSCP value, do you still trust the value at the remote peer.
For example, you connect into an MPLS with QoS enabled, you know that the values you are trusting are correct within your network, however at the remote peer/branch they could be remarked by the provider. Therefore do you 'believe' the values, or do you simply not trust them and then reclassify on ingress.
Regards
Allan.
Hope this makes sense..

QoS - can u trust dscp and cos?

Hello,
is it possible to trust DSCP and COS at the same time?
If so, which one wins?

G'day,
It does not really make sense to trust both DSCP and CoS at the same time. You configure your switch to trust one or none of these.
As an example, if you did have the capability to trust both DSCP and CoS, imagine what would happen if you received a frame with DSCP EF and CoS 0 ? You would be faced with a conflicting situation ... if you trusted CoS, you would give a potentially high-priority packet lesser service. Whereas if you trusted DSCP, you could end up giving a potentially low-priority packet voice-like service... So the option of trusting both is not allowed.
Hope that helps - pls rate the post if it does.
Paresh

What is the best way to trust DSCP values on 6509 interfaces?

I have 6509's with 2 Ten-gig interfaces configured into a Port Channel (routed with IP addressing) - the IOS is 12.2(18)SXE3. I want to trust the DSCP values of packets traveling through the interfaces and have applied 'mls qos trust dscp' on both the physical Ten-gig interfaces as well as the L3 Port Channel interface.
1.Is it necessary to have the statement on all the interfaces, or is just having it on the Port channel enough?
Here is the config right now:
interface Port-channel4
description to 6509-Core-A P4 (T1/3, T2/3)
ip address 164.xxx.xx.xx 255.255.255.252
ip pim sparse-mode
ip route-cache flow
mls qos trust dscp
interface TenGigabitEthernet1/1
description to 6509-Core-A T1/3 (P4)
no ip address
ip route-cache flow
mls qos trust dscp
channel-group 4 mode desirable
interface TenGigabitEthernet1/2
description to 6509-Core-A T2/3 (P4)
no ip address
ip route-cache flow
mls qos trust dscp
channel-group 4 mode desirable
Also, what command can I use to see the dscp counters? In the 3560/3750 catalyst line you can enter: 'sh mls qos int f0/1 statistics' and get a display of all the dscp/cos input/output packet counts, but I can't find a comparable command in the 6509.
2. Is there one?

I think you do this on the individual port interfaces, not the port-channel interface, becasue the queueing mechanisims associated with DSCP values are port based.
By doing this, if you have policy maps you want to use, you attach them to the ports not the port-channel.
For the command on 6509, you can use:
sh mls qos ip gigabitEthernet 1/1
Hope this helps and let me know how that works out.
Gary

Cat3560 and Trust DSCP Question

Hello,
we have several Cat3560 (IOS12.2.20SE4)as pure Layer-2 Switches in use. At these Switches are IP-Phones via a dot1q trunk connected (cisco and non-cisco Phones). The phones mark their traffic with COS=5 and DSCP=46.
Is it possible to configure a "mls qos trust dscp" at the switch-interfaces with IP-Phones, when the switchports are configured as Layer-2?
Of course the switches should also be able to put the traffic in the different receive and transmit-queues based on the received dscp-value.
We'd like configure QoS over our whole campus area DCSP-based and not CoS based to avoid the effort with the CoS<->DSCP mappings.
Thanks
HL

Hi,
Check if that helps.
http://www.cisco.com/univercd/cc/td/doc/product/lan/cat3560/12220se/3560scg/swqos.htm
HTH, Please rate if it does.
-amit singh

How to trust DSCP on 3Com 5500

Hi all,
I have a network with Cisco switches and 3Com switches...In the Cisco switches I trust the DSCP priority. I know, this is a Cisco forum but I need help about 3Com and I'm sure you can help me:
I have a 3Com 5500 with s4m03_03_02s168e.app and I want to trust the DSCP priority on a port of the switch.
How can I solve this. ¿With the command "priority trust" on the port the DSCP priority is trusted and the paquet goes to the internal queue?
I'm not sure because if I put this command I don't see changes on the port (display current-configuration)...
¿DSCP is trusted by default on all ports?
¿How can I view on what ports is trusted DSCP with a show command?
thanks all

Please get in touch with HP Forum or H3C forum to get your query answered.
This is purely Cisco devices forum.

QoS and DSCP settings for Video Streaming

So I've got this beautiful topology at home that consists of three WAP 121 and a RV320 as the default gateway.
How should I tweak their QoS and DSCP parameters to optimize Video Streaming applications like YouTube, Netflix and such?
Thanks community!

Open the set up page of the router by typing the IP address of 192.168.1.1 or open Cisco connection go to router settings
Then go to advanced settings and then click copy password and hit OK ..once you on the router page
Go to wireless and click manual after that create network name (SSID) Then set the wireless security as WPA2 personal
Which would give you stabilize connectivity then upgrade the latest firmware on the router and reduced the MTU to 1462..
Unplug the power from the modem and the router
Wait for 1 minute and plug them back wait for 1 minute and then check the speed .

Any one ever worked on 6500 series Cisco switches QOS or 6503 or 6524 QOS(Urgent help needed)

Hi All,
I am having issue specifally doing QOS configuration on 6503 or 6524 or 6509 switches. I am unable to match any EF(voice) traffic for eompls(vlan based) on 6503 cisco switch. If i use any other router as 2811 or 2821 my QOS configuration works perfect but if i put 6503 as PE2 it does not work.i am using vlan based eompls.
Below is the scenario & configuration which i am having issue.
CE1(2821 router)(dot1Q)--------->PE1(2821 router)------->P(6524 switch)-------->PE2(6503 switch)------->(dot1Q)(2821 switch)CE2.
On CE1 i can match ip-precedence 5 traffic and mark that traffic to cos5 on outbound port.On PE1 i can match cos5 packet and mark with mpls exp top5 on inbound port, on outbound port i can match mpls exp 5.
On PE2(6503) i am unable to match that mpls exp5 packet on inbound port. none of the configuration worked on 6500 series switches with mls qos, ,mls qos trust dscp,mls qos trust cos etc. Although i can match cos5 traffic on CE2 on inbound interface.i can not match mpls exp 5 traffic on 6503 and all i can see traffic as default-class on 6503 switch. I tried many things and many configurations on 6503 but nothing worked.If i put 2821 router as PE2 instead of 6503 my qos configuration works. but why if i put 6503 my same qos configuration does not work?
---match means=classification or classify
Can anyone tell me how qos works on 6500 series switches or where i am having issue in my scenario.
i am using this ios on 6503: s72033-advipservicesk9_wan-mz.122-33.SXI3.bin.
below r my questions for 6503 qos:
1.do i need to use some other map tables,am i using correct map tables on 6503 as cos-dscp,dscp-cos,exp-dscp etc.
2.any other configutaion of qos needed on 6503?
3.i am unable to match anything on outbound port of 6503.
4.on 6503 i am using sup720 and PFC3BXL.any specific configuration needed for PFC3bxl.
5. 6503 not allowing me to match qos-group on inbound interface, not allowing me to set cos5 on outbound interface. not allowing me to set cos5 as an inbound interface.
CE1(2821) config:
class-map match-any EF
match ip precedence 5
class-map match-any data
match ip precedence 3
policy-map ip2mpls
class EF
set cos 5
class data
set cos 3
interface FastEthernet0/0
no ip address
duplex auto
speed auto
interface FastEthernet0/0.455
encapsulation dot1Q 455
ip address 172.16.15.1 255.255.255.252
service-policy output EF
PE1(2821) config:
mls qos map cos-dscp 0 8 16 24 32 40 48 56
class-map match-all exp_3
match mpls experimental topmost 3
class-map match-all mpls_exp
match mpls experimental topmost 5
class-map match-any cos3
match cos 3
class-map match-any LOO1
match cos 5
policy-map EF
class LOO1
set mpls experimental imposition 5
class cos3
set mpls experimental imposition 3
policy-map QOS_G_5
class mpls_exp
priority
class exp_3
bandwidth 500
interface Loopback0
ip address 3.3.3.3 255.255.255.255
interface FastEthernet0/0
ip address 192.168.23.2 255.255.255.0
ip ospf network point-to-point
duplex auto
speed auto
mpls ip
service-policy output QOS_G_5
interface FastEthernet0/1.455
encapsulation dot1Q 455
xconnect 5.5.5.5 455 encapsulation mpls
service-policy input EF
PE2(6503 qos):
R1#show module
Mod Ports Card Type Model Serial No.
1 4 CEF720 4 port 10-Gigabit Ethernet WS-X6704-10GE SAL09401U2L
2 48 CEF720 48 port 10/100/1000mb Ethernet WS-X6748-GE-TX SAL114247YN
3 16 16 port 1000mb GBIC ethernet WS-X6416-GBIC SAL0712AM69
4 24 CEF720 24 port 1000mb SFP WS-X6724-SFP SAL10019J4N
5 2 Supervisor Engine 720 (Hot) WS-SUP720-3BXL SAD102805VM
6 2 Supervisor Engine 720 (Active) WS-SUP720-BASE SAD0846060F
Mod Sub-Module Model Serial Hw Status
1 Distributed Forwarding Card WS-F6700-DFC3BXL SAD102504EF 5.3 Ok
2 Centralized Forwarding Card WS-F6700-CFC SAD111300PD 3.1 Ok
4 Centralized Forwarding Card WS-F6700-CFC SAL1004BQ2A 2.0 Ok
5 Policy Feature Card 3 WS-F6K-PFC3BXL SAD10270189 1.8 Ok
5 MSFC3 Daughterboard WS-SUP720 SAD102801G5 2.5 Ok
6 Policy Feature Card 3 WS-F6K-PFC3BXL SAL1415FE95 1.11 Ok
6 MSFC3 Daughterboard WS-SUP720 SAD08440794 2.4 Ok
R1#show mls qos maps
Normal Burst Policed-dscp map: (dscp= d1d2)
d1 : d2 0 1 2 3 4 5 6 7 8 9
0 : 01 01 02 03 04 05 06 07 08 09
1 : 10 11 12 13 14 15 16 17 18 19
2 : 20 21 22 23 24 25 26 27 28 29
3 : 30 31 32 33 34 35 36 37 38 39
4 : 40 41 42 43 44 45 01 47 48 49
5 : 50 51 52 53 54 55 56 57 58 59
6 : 60 61 62 63
Maximum Burst Policed-dscp map: (dscp= d1d2)
d1 : d2 0 1 2 3 4 5 6 7 8 9
0 : 00 01 02 03 04 05 06 07 08 09
1 : 10 11 12 13 14 15 16 17 18 19
2 : 20 21 22 23 24 25 26 27 28 29
3 : 30 31 32 33 34 35 36 37 38 39
4 : 40 41 42 43 44 45 46 47 48 49
5 : 50 51 52 53 54 55 56 57 58 59
6 : 60 61 62 63
Dscp-cos map: (dscp= d1d2)
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
Dscp-exp map: (dscp= d1d2)
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
Cos-dscp map:
cos: 0 1 2 3 4 5 6 7
dscp: 0 10 18 24 34 46 48 56
IpPrecedence-dscp map:
ipprec: 0 1 2 3 4 5 6 7
dscp: 0 8 16 24 32 40 48 56
Exp-dscp map:
exp: 0 1 2 3 4 5 6 7
dscp: 0 8 16 24 32 40 48 56
mls netflow interface
mls qos map cos-dscp 0 10 18 24 34 46 48 56
mls qos
class-map match-all exp_3
match mpls experimental topmost 3
class-map match-all EXP_5
match mpls experimental topmost 5
class-map match-all QOS_GROUP_5
match qos-group 5
class-map match-all prec5
match ip precedence 5
class-map match-all cos5
match cos 5
policy-map mpls2ip
class QOS_GROUP_5
set cos 5
policy-map IN_FROM_R3
class EXP_5
set qos-group 5
interface Loopback0
ip address 5.5.5.5 255.255.255.255
interface GigabitEthernet2/2
mls qos trust cos
or <------------ (tried both individually but none worked)
mls qos trust dscp
interface GigabitEthernet2/2.455
encapsulation dot1Q 455
xconnect 3.3.3.3 455 encapsulation mpls
service-policy output mpls2ip
interface GigabitEthernet2/1
ip address 192.168.34.4 255.255.255.0
ip ospf network point-to-point
mls qos trust cos
or <------------ (tried both individually but none worked)
mls qos trust dscp
mpls ip
service-policy input IN_FROM_R4
Thanks & regards,
Ahsan Rasheed

Hi All,.
I am still having issue on 6503 or 6524 Cisco Switch.
" Can any one give me any sample of 6524 or 6503 QOS working configuration, i would be really thankful "
As i have mentioned in my prevoius post of configuration of 6503. I am unable to match mpls exp 5 packet on 6503. My qos configuration on PE1(2811 router) is working perfectly. I am unable to classify mpls ex5 or mpls exp3 on 6503 switch. Am i missing something on configuration?
PE2 config:"6503 switch"
class-map match-all mpls_exp
match mpls experimental topmost 5
policy-map EF
class mpls_exp
R!#mls qos
int Gi2/4
service-policy input EF
mls qos trust cos
dscp: 0 10 18 24 34 46 48 56
Exp-dscp map:
exp: 0 1 2 3 4 5 6 7
dscp: 0 10 18 24 34 46 48 56
Thanks,
Ahsan Rasheed

After i plug in my iphone 5s, it always asks me to trust the laptop, i click trust and my laptop makes that noise as if I've pulled my phone out, but i haven't, so now my itunes doesn't recognize my phone, please please help me?

After i plug in my iphone 5s, it always asks me to trust the laptop, i click trust and my laptop makes that noise as if I've pulled my phone out, but i haven't, so now my itunes doesn't recognize my phone, please please help me?
THis also happened with my old iphone 4s
I need help!

Hi loist,
Thanks for visiting Apple Support Communities.
If your iPhone is not being recognized by your computer after you click "Trust," the troubleshooting steps found here can help:
iOS: Device not recognized in iTunes for Windows
http://support.apple.com/kb/TS1538
Cheers,
Jeremy

"mls qos trust dscp" vs. "mls qos trust cos"

Similar Messages

Maybe you are looking for