MLS QoS configuration

Good Morning, everyone. I am looking for some clarification with an existing 3750x Switch configuration.
I am reviewing the configuration of my network switches and found the following MLS QoS configuration on one of my switches and a partial of this same config on another switch. Can someone please explain what function, this line of code, is performing; and is it necessary?
mls qos map policed-dscp 0 14 24 30 38 to 8
mls qos map policed-dscp 10 to 12
mls qos map policed-dscp 12 to 14
mls qos map policed-dscp 26 to 28
mls qos map policed-dscp 28 to 30
mls qos map policed-dscp 32 to 34
mls qos map policed-dscp 34 to 36
mls qos map policed-dscp 36 to 38
mls qos map cos-dscp 0 8 16 24 34 46 48 56
mls qos srr-queue input bandwidth 70 30
mls qos srr-queue input threshold 1 80 90
mls qos srr-queue input threshold 2 80 90
mls qos srr-queue input priority-queue 2 bandwidth 30
mls qos srr-queue input dscp-map queue 1 threshold 2 16 24
mls qos srr-queue input dscp-map queue 1 threshold 3 48 56
mls qos srr-queue input dscp-map queue 2 threshold 1 36 38
mls qos srr-queue input dscp-map queue 2 threshold 2 32 34
mls qos srr-queue input dscp-map queue 2 threshold 3 40 46
mls qos srr-queue output cos-map queue 1 threshold 2 4
mls qos srr-queue output cos-map queue 1 threshold 3 5
mls qos srr-queue output cos-map queue 2 threshold 1 2
mls qos srr-queue output cos-map queue 2 threshold 2 3
mls qos srr-queue output cos-map queue 2 threshold 3 6 7
mls qos srr-queue output cos-map queue 3 threshold 3 0
mls qos srr-queue output cos-map queue 4 threshold 3 1
mls qos srr-queue output dscp-map queue 1 threshold 2 32 34
mls qos srr-queue output dscp-map queue 1 threshold 3 40 46
mls qos srr-queue output dscp-map queue 2 threshold 1 18 20 22 26 28 30
mls qos srr-queue output dscp-map queue 2 threshold 2 16 24
mls qos srr-queue output dscp-map queue 2 threshold 3 48 56
mls qos srr-queue output dscp-map queue 3 threshold 3 0
mls qos srr-queue output dscp-map queue 4 threshold 1 8
mls qos srr-queue output dscp-map queue 4 threshold 2 12 14
mls qos srr-queue output dscp-map queue 4 threshold 3 10
mls qos queue-set output 1 threshold 1 100 100 100 100
mls qos queue-set output 1 threshold 2 80 90 100 400
mls qos queue-set output 1 threshold 3 100 100 100 400
mls qos queue-set output 1 threshold 4 90 100 100 400
mls qos queue-set output 1 buffers 15 30 35 20
mls qos
If more information is required for a response, please let me know.
Thank you, E.

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
The function of each command is perhaps best explained by the Command Reference and Software Configuration Guide for your IOS version. If you have a question that's unanswered by those, please post another question. BTW, Cisco also publishes whitepapers that further explain some subjects. There are a couple on 3750 QoS.
Regarding whether a particular command is necessary would depend on what your QoS policy is attempting to accomplish.

Similar Messages

Version 03.03.00.XO - MLS QOS not supported

Hi All,
Anyone face the same problem with the following IOS Version?
MLS QOS is not supported in global command.
Switch#sh ver
Cisco IOS Software, IOS-XE Software, Catalyst 4500 L3 Switch Software (cat4500es8-UNIVERSALK9-M), Version 03.03.00.XO RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2013 by Cisco Systems, Inc.
Compiled Wed 14-Aug-13 07:26 by prod_rel_team
Cisco IOS-XE software, Copyright (c) 2005-2013 by cisco Systems, Inc.
All rights reserved. Certain components of Cisco IOS-XE software are
licensed under the GNU General Public License ("GPL") Version 2.0. The
software code licensed under GPL Version 2.0 is free software that comes
with ABSOLUTELY NO WARRANTY. You can redistribute and/or modify such
GPL code under the terms of GPL Version 2.0. For more details, see the
documentation or "License Notice" file accompanying the IOS-XE software,
or the applicable URL provided on the flyer accompanying the IOS-XE
software.
ROM: 15.1(1r)SG2
Switch uptime is 6 minutes
System returned to ROM by power-on
Running default software
Jawa Revision 3, RadTrooper Revision 0x0.0x41, Conan Revision 0x1449
Last reload reason: power-on
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
[email protected].
License Information for 'WS-X45-SUP8-E'
License Level: entservices Type: Permanent
Next reboot license Level: entservices
cisco WS-C4506-E (P5040) processor (revision 2) with 4194304K bytes of physical memory.
Processor board ID FXS1812Q346
P5040 CPU at 2.2GHz, Supervisor 8-E
Last reset from PowerUp
1 Virtual Ethernet interface
20 Ten Gigabit Ethernet interfaces
511K bytes of non-volatile configuration memory.
Configuration register is 0x2101
SWITCH(config)#mls qos
                     ^
% Invalid input detected at '^' marker.
SWITCH(config)#
SWITCH(config)#?
Configure commands:
aaa                         Authentication, Authorization and Accounting.
access-list                 Add an access list entry
access-session              Access Sesion Global Configuration Commands
agent-server                Modify DNS server properties
alias                       Create command alias
ancp                        Configure ANCP
archive                     Archive the configuration
arp                         Set a static ARP entry
async-bootp                 Modify system bootp parameters
audit                       Router Audit
authentication              Auth Manager Global Configuration Commands
auto                        Configure Automation
banner                      Define a login banner
beep                        Configure BEEP (Blocks Extensible Exchange
                              Protocol)
bfd                         BFD configuration commands
bfd-template                BFD template configuration
boot                        Modify system boot parameters
bridge                      Bridge Group.
buffers                     Adjust system buffer pool parameters
bulkstat                    Bulkstat Application
call-home                   Enter call-home configuration mode
cdp                         Global CDP configuration subcommands
cef                         Cisco Express Forwarding
cisp                        Set CISP parameters
class-map                   Configure CPL Class Map
clns                        Global CLNS configuration subcommands
clock                       Configure time-of-day clock
cluster                     Cluster configuration commands
cns                         CNS agents
comet-server                Configure comet-server properties
config-register             Define the configuration register
configuration               Configuration access
control-plane               Configure control plane services
crypto                      Encryption module
cts                         Cisco Trusted Security commands
default                     Set a command to its defaults
default-value               Default character-bits values
define                      interface range macro definition
device-sensor               IOS Sensor Commands
diagnostic                  Configure diagnostic information
dns-server                  Modify DNS server properties
dnsix-dmdp                  Provide DMDP service for DNSIX
dnsix-nat                   Provide DNSIX service for audit trails
do-exec                     To run exec commands in config mode
dot1x                       IEEE 802.1X Global Configuration Commands
downward-compatible-config Generate a configuration compatible with older
                              software
eap                         EAP Global Configuration Commands
emm                         Specify pre-loading of MDF
enable                      Modify enable password parameters
end                         Exit from configure mode
energywise                  EnergyWise Global Configuration Commands
epm                         EPM Global Configuration Commands
errdisable                  Error disable
ethernet                    Ethernet configuration
event                       Event related configuration commands
exception                   Exception handling
exit                        Exit from configure mode
fallback                    Fallback configuration commands
fhrp                        Configure First Hop Redundancy Protocols
file                        Adjust file system parameters
fips                        FIPS mode after next reload
flow                        Global Flow configuration subcommands
format                      Format the output
global-address-family       Enter address-family base routing topology mode
help                        Description of the interactive help system
hostname                    Set system's network name
hw-module                   Apply command (e.g. shutdown) to specified
                              hardware target
hw-module                   Control of individual components in the system
hw-switch                   Control of individual components in the switch
id-manager                  ID Pool Manager
identity                    Identity Configuration Commands
infra-test                  Configure end2end properties
interface                   Select an interface to configure
ip                          Global IP configuration subcommands
ipc                         Configure IPC system
ipv6                        Global IPv6 configuration commands
isis                        Global ISIS configuration subcommands
issu                        no description
key                         Key management
kron                        Kron interval Facility
l2                          Layer 2
l2protocol-tunnel           Tunnel Layer2 protocols
lacp                        LACP configuration
li-view                     LI View
license                     Configure License
line                        Configure a terminal line
link                        Enable Link State Tracking feature
lldp                        Global LLDP configuration subcommands
location                    Global location configuration commands
logging                     Modify message logging facilities
login                       Enable secure login checking
mab                         MAC Authentication Bypass Global Configuration
                              Commands
mac                         Global MAC configuration subcommands
macro                       Macro configuration
media-proxy                 Global media proxy configuration
mediatrace                  Mediatrace Application
memory                      Configure memory management
metadata                    Metadata Application
mka                         MACsec Key Agreement (MKA) configuration
module                      Module
monitor                     Monitoring different system events
mvr                         Enable/Disable MVR on the switch
netconf                     Configure NETCONF
Thank you.

Hi,
QOS implementation has radically changed since the advent of
sup-7 & later
You no longer set mls qos as qos is on the engine by default.
Please see the following links
http://www.cisco.com/c/en/us/products/collateral/switches/catalyst-4500-series-switches/white_paper_c11-539588.html
"Ingress QoS: Default Actions
First and foremost, QoS does not need to be enabled on the Supervisor Engine, it is on by default in compliance with the MQC construct.
When a packet arrives at an interface, there are two options to take into consideration: is there a policy attached or not? If the packet arrives with or without a marking and there is not a policy attached to the interface, packets will flow through the switch untouched. There are no questions as to where the packet came from or if it has a valid marking. If the packet arrives with or without a marking, and a policy is attached to the interface, the packet will only then be subject to the policy classification."
And the config guide
http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst4500/15-1/XE_330SG/configuration/guide/config/qos_mrg.html#wp1461453
Hope this helps
Regards
Alex

QOS configuration

To enable to QOS feature globally on switches, the command below should be applied on the core switches or the POE switches that connected to the core switches?
Switch(config)#mls qos
POE switches:
Switch(config)#interface GigabitEthernet <interface ID>
Switch(config-if)#auto qos voip trust
Any other command can be used to verify whether it is configured successfully?

the "auto qos voip trust" command applies to the core switch.
trust —When you enter the auto qos voip trust interface configuration command on a port connected to the interior of the network, the switch trusts the CoS value in ingress packets (the assumption is that traffic has already been classified by other edge devices).
link:
http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book/QoSDesign.html
You can use "sh run int gix/x to verify the config.
HTH

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

Mls qos VS mls qos trust

Hello world!
I want to enable qos on a 3560 switch,
So, I put:
Overall setup mode "mls qos"
Question:
is what it is Verily nessaiire to interface configuration mode: "mls qos trust"?
Regards,

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Generally, on many Catalyst switches, once you enable QoS, they will erase an ingress CoS/ToS markings unless your trust it or otherwise (i.e. policy) maintain it.
I.e. the answer to your question is an "it depends"; but unless you want the markings reset to zero, the answer is probably yes (you want to trust).

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..

Mls qos trust

Hello, if the command 'mls qos trust xxxxx' is not issued, and qos is turned on for the interface, does this mean the switch will erase all cos and dscp markings received, therefore preventing me from testing packets/frames against these cos/dscp values ?
So if I want to set up class maps, policy maps, and then service policies, it is essential that I:
1. turn on mls qos ?
2. enter a trust statement in order to preserve the cos or dscp values that I want to test against ?
3. now I can test against against cos or dscp values ?
Thanks for clarification.

That is correct, when you would use for instance mls qos trust cos. You would need to define you cos<>dscp mappings on the switch and the switch will apply qos accordingly.
So really if you have an ingress switch port and you trust cos or dscp, you can still have egress policies on a port (on the same switch), using these cos or dscp values.
the mls qos trus command is just a way to make it easier to rely on existing cos/dscp values that a phone sends (based on your CUCM configuration,), without the need for you having to configure it explicitly on each access port.
=============================
Please remember to rate useful posts, by clicking on the stars below.
=============================

Mls qos trust{cos/ip-precedence/dscp} command

Hi every body!
I have few questions
1)
The command " mls qos trust dscp" is only valid on mulilayer switch or it is also valid for layer 2 switch? If layer 2 switch is configured with that command, can it modify the dcsp value based on policy?
2)is the following correct:
switch(config-if) mls qos trust dscp
switch will set the cos value to set default. If the default set is zero, then frame will be processed by best-effort delivery.
But the egress-queue will be decided by dscp value in the packet. A dscp to cos map will be used to drive the cos value and then frame will be placed in the queue that corresponds to cos value.( off course if egress port is configured for trunk)
thanks a lot and I wish America and all of you a happy new year!
thanks a lot!

Sarah
1) L2 switches can trust the dscp marking as well. The 2960 is a layer 2 only switch and the default is untrusted but if you then enter
"mls qos trusted" you have a choice of 'cos|dscp|ip-precedence'. The default if no choice is entered is DSCP.
2) If "mls qos trust dscp" is entered then the switch will use the DSCP marking found in the packet. This will then be used as the internal DSCP marking that all switches use. Unless you have a DSCP-DSCP mutation map the value used will be the value received in the packet.
Jon

Mls qos trust cos vs mls qos cos in cat6k

Hello
I am trying to configure basic qos topology with two 6k connected to each other by the trunk port.
According to the documentation, if I set the mls qos cos value at the interface level I should modify the default cos on it, and all packets leaving incoming to this port, should be marked with the new cos value.
http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6000-series-switches/24055-173.html
Unfortunately, when I set such config, all incoming packets transmitted through this interface was tagged with cos = 0 until I set the "mls qos trust cos" on the same interface.
Does anybody can explain to me this strange behavior?
I would like to mention that both 6k was connected to each other with ws-x6548-GE-TX modules.
Thank you in advance.
Ragards
Lukas

Sarah
1) L2 switches can trust the dscp marking as well. The 2960 is a layer 2 only switch and the default is untrusted but if you then enter
"mls qos trusted" you have a choice of 'cos|dscp|ip-precedence'. The default if no choice is entered is DSCP.
2) If "mls qos trust dscp" is entered then the switch will use the DSCP marking found in the packet. This will then be used as the internal DSCP marking that all switches use. Unless you have a DSCP-DSCP mutation map the value used will be the value received in the packet.
Jon

Mls qos enabled globally and disabled for only one interface

Hello !
My switch is Cisco IOS Software, C2960X Software (C2960X-UNIVERSALK9-M), Version 15.0(2)EX5, RELEASE SOFTWARE (fc1)
I try to disabled mls qos only for one interface, but when i do it, mls qos is globally disabled. Is it possible to do it ?
XXX#show mls qos
QoS is enabled
QoS ip packet dscp rewrite is enabled
XXX#conf t
Enter configuration commands, one per line. End with CNTL/Z.
XXX(config)#interface gigabitEthernet 1/0/5
XXX(config-if)#no mls qos
XXX(config)#exit
XXX#
XXX#show mls qos
QoS is disabled
QoS ip packet dscp rewrite is enabled
Thanks in advance for your help !!
Denis

Hi Denis,
You cant disable the QOS on per interface on 2960 devices.
By default, QoS is disabled. When we enable QoS all ports
will be assigned to queue-set 1. We can configure up to two
different queue-sets.
Hence if you remove the qos out of the interface it would be disabled globally as well.
HTH

Help in QoS configuration on 3750E/2960X

Hello everybody,
I would like to configure QoS in VoIP for terminal Aastra in switches Cisco (with L3). As I am not very confident in this issue, I have thought to give a priority for VoIP considering output traffic from IP telephone. The IP telephones have an IP in range 10.5.160.0/22, so could it be this criteria valid for assigning QoS to the VoIP packets? The criteria would be:
ip access-list extended tel_VOIP
permit tcp 10.5.160.0 0.0.0.252 any
permit udp 10.5.160.0 0.0.0.252 any
Class-map match-all VOIP
Match access-group name tel_VOIP
Policy-map VOIP
Class VOIP
Set ip dscp 32
And then for the access voip ports, I would put this:
Interface giga0/x
switchport mode access
service-policy input VIDEO
service-policy output VOIP
switchport voice vlan 6
switchport access vlan n
mls qos trust dscp
power inline consumption 5000
Also I have another policy-map configured for input traffic for video which gives it pri 32.
I would like to know if traffic with maximum priority goes by queue out nº 1 by default. And if so, if this would be enough to guarantee video and voip traffic would go by this queue, which has by default 4 Mb shaped. Our video only takes 256Kb.
Another thing is if more than 4 Mb were needed in queue out, a way to assure video and voip traffic would be to configure this queue as priority queue-out, wouldn’t it be?
Please, I do not know how to configure queues and I only want to know if this would categorize voip and video traffic with a dscp of 32.
Thank you very much.
I am a bit lost about this item. And that is why I would prefer not configuring different weights for the out queues if not necessary. Please, make me any comment. I could send you my configuration.

hello Yahsiel,
Well, I must have mismatched signaling value with voice traffic value. What I would like to do is marking voip traffic and then reserving a bandwith for it.
I have investigated and voip traffic comes marked with CoS 5, so I suppose I do not have to create an access-list, I could create a class-map for voip:
class-map VOIP
match ip precedence 5
and then reserve BW for it:
policy-map VOIP-VIDEO
Class VOIP
priority 1000
and then I could also set this policy in all the access ports with:
service-policy input VOIP-VIDEO
I suppose I could include in this same policy-map the marking of VIDEO traffic which is:
class VIDEO
set ip dscp 32
Also as you say I will have to put in the access ports the "mls qos trust cos" and in the trunk "mls qos trust dscp".
Do you think now this would guarantee 1 Mb for voip in the out queue? Out queue 1 has a total of 4 Mb maximum shaped so I think this would run....
What about "auto qos voip trust" in the interface level for all the ports? Some people tell me this run ok, but I do not know if I must configure it or not. If I configured auto qos, I think I wouldn't have to policy voip traffic.
Thank you for your soon reply. Really!!!

Catalyst 3550 & 3560/3750 command 'show mls qos interface statistics'

On the Catalyst 3550 the command 'show mls qos interface statistics' will show ingress packet (or byte) counts with DSCP values. If you have policers configured then it also shows a count of packets that have been marked down to another DSCP value due to policing or any that have been dropped (obviously 'mls qos monitor dscp x' needs configuring). The same command on the 3560/3750 only shows the ingress & egress DSCP values, there is no column that shows packets (or bytes) that have been policed or dropped. Is there any command to display the same information with the 3560/3750?
Neither platform show counters when the command 'show policy-map interface x/x' is used so this won't work.
Thanks
Andy

Hi, I believe there is a command on the 3560 'sh mls qos interface policers' may be what you are looking for.
Here is what the command says it outputs:
To display QoS information at the interface level. This information includes:
The configuration of the egress queues and the CoS3-to-egress-queue map
Which interfaces have configured policers
Ingress and egress statistics, which includes the number of bytes that have been dropped

Switchport QoS configuration for WLC

Hi guys,
I am having a question about switchport QoS configuration for WLC. In the "enterprise mobility deployment guide 4.1", it says we can use both either "mls qos trust cos" or "mls qos trust dscp", depending on the mapping, however looking through Jerome's video tutorial on QoS in youtube, he actually mentioned that we need to keep this value as "mls qos trust cos", and I have also read from somewhere else that since controllers are layer 2 device, we do need to use "mls qos trust cos" on the switchport directly connected to the WLC.
however I did see some configurations using "mls qos trust dscp" on the switchport, which is for 5508 WLC due to some hardware design in the 5508 WLC. so I just want to ask what is the differnece between these two commands when we use them for switchports connected to WLC, and does this command really specific for what controller platform we use or it only depends on code version?
thank you very much for your time and help.

Hi George,
Thanks for your reply, however I am still a bit confused on the difference between the two commands...
so in the deployment guide it does say we can do either one on the switchports connected to the WLC, so when should we use trust dscp instead of cos?
it sort of make sense when we talk about WLC is a layer 2 device hence we should use cos, but we also have packets marked with dscp values and I think the controller will keep the value without any modification, then that means we can also use trust dscp in order for this mapping to be done correctly, is this correct?
I did see some other people saying that when using turst dscp and did a packet capture, the values cannot be mapped correctly, but there are also cases that this works. expecially with 5508 series controllers, does it really have some hardware features that doing different things than the 4404s and the 2100 series?
but still, in what situation should we trust dscp on switchports connecting to WLC and when should we use trust cos as a best practice? or we should just forget about trust dscp for switchport connecting to WLC?
Thanks.

About QoS configurable thresholds...

Hey,
I was reading through QoS guides and got confused about the threshold things.......
According to document,
you can use following command to configure maximum memory allocation for egress queue.
mls qos queue-set output qset-id threshold queue-id drop-threshold1 drop-threshold2 reserved-threshold maximum-threshold
you can use following command to configure allocated memory for egress queue.
mls qos queue-set output qset-id buffers allocation1 ... allocation4
So now questions:
1. Why queue-set? There will be 4 queue for egress anyway...
2. If queue-set is useful feature, Why no queue-set for ingress?
3. Why multiple thresholds? For ingress, there will be one threshold per queue.
4. When is drop-threshold1 used? When will drop-threshold2 used?
Thanks,
/S

Disclaimer
The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
Liability Disclaimer
In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
Posting
Or, perhaps this isn't the best forum for this question.
See if this document helps: https://supportforums.cisco.com/docs/DOC-8093

Without 'MLS QOS' in 6500 does any interface queueing and trusting take place?

I have a 6500 that does not have 'mls qos' global configured, although the interfaces do have 'mls qos trust dscp' on them as in:
interface GigabitEthernet3/3
switchport
switchport access vlan 536
switchport mode access
switchport voice vlan 910
logging event link-status
mls qos trust dscp
spanning-tree portfast
When I 'show queueing int gx/x', it does show the default queueing structure of the interface as in:
LLT-6509AS-A#sh queueing int g3/3
Interface GigabitEthernet3/3 queueing strategy: Weighted Round-Robin
QoS is disabled globally
Port is untrusted
Extend trust state: not trusted [COS = 0]
Default COS is 0
    Queueing Mode In Tx direction: mode-cos
    Transmit queues [type = 1p3q8t]:
    Queue Id    Scheduling Num of thresholds
       01         WRR                 08
       02         WRR                 08
       03         WRR                 08
       04         Priority              01
---- snip ----
    queue thresh cos-map
    1     1      0 1 2 3 4 5 6 7
    1     2
    1     3
    1     4
    1     5
    1     6
    1     7
    1     8
Packets dropped on Transmit:
    BPDU packets: 0
    queue              dropped [cos-map]
    1                        0 [0 1 2 3 4 5 6 7 ]
    2                        0 []
    3                        0 []
    4                        0 []
Packets dropped on Receive:
    BPDU packets: 0
    queue              dropped [cos-map]
    1                        0 [0 1 2 3 4 5 6 7 ]
So just what does the global 'mls qos' do? Without it is the command 'mls qos trust dscp' ignored?
I'm trying to track down where in our network dscp settings are being stripped out of packets and this is when I noticed the 'mls qos' was not configured.

it enables QOS on the switch, without it no QOS is being used.
Sent from Cisco Technical Support iPhone App

MLS QoS configuration

Similar Messages

Maybe you are looking for