ciscocisco-catalystcisco-commandsqosswitch
I'm testing some Cisco 3650 switches with Cisco VoIP handsets and using auto qos. Is there a way to see if qos is kicking in and prioritising the voice traffic? Tried looking through the cli and can't find anything.
Thanks for reading, appreciate any advice.
Cisco has something they call Cisco Validated Designs (CVD). These are network designs from different perspectives like QoS, high availability, WAN etc that Cisco recommends and have tested.
For QoS they have 3 different designs with 4, 8 or 12 classes which can be seen in the picture below.
Starting with the 4 class model:
! This section defines the 4-Class class-maps
! (three are explicitly defined and one is default)
Router(config)# class-map match-any REALTIME
Router(config-cmap)# match dscp ef
! Matches VoIP
Router(config-cmap)# match dscp cs5
! Matches Broadcast Video
Router(config-cmap)# match dscp cs4
! Matches Realtime-Interactive
Router(config)# class-map match-any CONTROL
Router(config-cmap)# match dscp cs6
! Matches Network-Control
Router(config-cmap)# match dscp cs3
! Matches Signaling (control-plane traffic for voice/video infrastructure)
Router(config-cmap)# match dscp cs2
! Matches Network Management
Router(config)# class-map match-any CRITICAL-DATA
Router(config-cmap)# match dscp af41 af42 af43
! Matches Multimedia Conferencing on AF4
Router(config-cmap)# match dscp af31 af32 af33
! Matches Multimedia Streaming on AF3
Router(config-cmap)# match dscp af21 af22 af23
! Matches Transactional Data on AF2
Router(config-cmap)# match dscp af11 af12 af13
! Matches Bulk Data on AF1
! This section defines the 4-Class Policy-Map
Router(config)# policy-map WAN-EDGE-4-CLASS
Router(config-pmap)# class REALTIME
Router(config-pmap-c)# priority percent 33
! Provisions 33% LLQ for REALTIME class
Router(config-pmap-c)# class CONTROL
Router(config-pmap-c)# bandwidth percent 7
! Provisions 7% CBWFQ for CONTROL class
Router(config-pmap-c)# class CRITICAL-DATA
Router(config-pmap-c)# bandwidth percent 35
! Provisions 35% CBWFQ for CRITICAL-DATA class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on CRITICAL-DATA class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on CRITICAL-DATA class
Router(config-pmap-c)# random-detect dscp af11 50 64
! Tunes WRED min and max drop-thresholds for AF11/10 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af12 45 64
! Tunes WRED min and max drop-thresholds for AF12/12 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af13 40 64
! Tunes WRED min and max drop-thresholds for AF13/14 to 40 and 64 packets
Router(config-pmap-c)# random-detect dscp af21 50 64
! Tunes WRED min and max drop-thresholds for AF21/18 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af22 45 64
! Tunes WRED min and max drop-thresholds for AF22/20 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af23 40 64
! Tunes WRED min and max drop-thresholds for AF23/22 to 40 and 64 packets
Router(config-pmap-c)# random-detect dscp af31 50 64
! Tunes WRED min and max drop-thresholds for AF31/26 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af32 45 64
! Tunes WRED min and max drop-thresholds for AF32/28 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af33 40 64
! Tunes WRED min and max drop-thresholds for AF33/30 to 40 and 64 packets
Router(config-pmap-c)# random-detect dscp af41 50 64
! Tunes WRED min and max drop-thresholds for AF41/34 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af42 45 64
! Tunes WRED min and max drop-thresholds for AF42/36 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af43 40 64
! Tunes WRED min and max drop-thresholds for AF43/38 to 40 and 64 packets
Router(config-pmap-c)# class class-default
Router(config-pmap-c)# bandwidth percent 25
! Provisions 25% CBWFQ for default (Best-Effort) class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on default (Best-Effort) class
Router(config-pmap-c)# queue-limit 128 packets
! Expands queue-limit to 128 packets
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on default (Best-Effort) class
Router(config-pmap-c)# random-detect dscp default 100 128
! Tunes WRED min and max drop-thresholds for DF/0 to 100 and 128 packets
Router(config-pmap-c)# random-detect dscp cs1 60 100
! Tunes WRED min and max drop-thresholds for CS1/8 to 60 and 100 packets
As you can see it matches on different DSCP values. DSCP EF is generally used for VoIP. This means that your packets should already have been marked as early as possible in your network. The bandwidth values are entered in percent which means that the policy can applied on different speed interfaces and still provide good values compared to entering them in kbit/s. On very high speed interfaces like 10 Gbit it could be a lot to use 7% for control traffic though since that would be 700 Mbit/s.
Both the data and the class-default uses fair-queue which is a way of queueing packets based on DSCP and packet size to provide fair queueing even for small packet flows. To be able to use this you need an image supporting Hierarchical Queing Framework (HQF) which is 12.4(20)T or newer.
Weighted Random Early Detection (WRED) is also applied to take care of issues like TCP synchronization where TCP flows will speed up and back off at the same time.
Then you have the 8 class model.
! This section defines the 8-Class class-maps
! (seven are explicitly defined and one is default)
Router(config)# class-map match-all VOICE
Router(config-cmap)# match dscp ef
! Matches VoIP
Router(config)# class-map match-any INTERACTIVE-VIDEO
Router(config-cmap)# match dscp cs5
! Matches Broadcast Video
Router(config-cmap)# match dscp cs4
! Matches Realtime-Interactive
Router(config)# class-map match-any NETWORK-CONTROL
Router(config-cmap)# match dscp cs6
! Matches Network Control
Router(config-cmap)# match dscp cs2
! Matches Network Management
Router(config)# class-map match-all SIGNALING
Router(config-cmap)# match dscp cs3
! Matches Signaling
Router(config)# class-map match-all MULTIMEDIA-STREAMING
Router(config-cmap)# match dscp af31 af32 af33
! Matches Multimedia-Streaming on AF3
Router(config)# class-map match-any CRITICAL-DATA
Router(config-cmap)# match dscp af41 af42 af43
! Matches Multimedia-Conferencing on AF4
Router(config-cmap)# match dscp af21 af22 af23
! Matches Transactional-Data on AF2
Router(config-cmap)# match dscp af11 af12 af13
! Matches Bulk-Data on AF1
Router(config)# class-map match-all SCAVENGER
Router(config-cmap)# match dscp cs1
! Matches Scavenger
! This section configures the 8-class policy-map
Router(config)# policy-map WAN-EDGE-8-CLASS
Router(config-pmap)# class VOICE
Router(config-pmap-c)# priority percent 10
! Provisions 10% LLQ for VOICE class (dual LLQ-policy)
Router(config-pmap-c)# class INTERACTIVE-VIDEO
Router(config-pmap-c)# priority percent 23
! Provisions 23% LLQ for INTERACTIVE-VIDEO class (dual-LLQ policy)
Router(config-pmap-c)# class NETWORK-CONTROL
Router(config-pmap-c)# bandwidth percent 5
! Provisions 5% CBWFQ for NETWORK-CONTROL class
Router(config-pmap-c)# class SIGNALING
Router(config-pmap-c)# bandwidth percent 2
! Provisions 2% CBWFQ for SIGNALING class
Router(config-pmap-c)# class MULTIMEDIA-STREAMING
Router(config-pmap-c)# bandwidth percent 10
! Provisions 10% CBWFQ for MULTIMEDIA-STREAMING class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on MULTIMEDIA-STREAMING class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on MULTIMEDIA-STREAMING class
Router(config-pmap-c)# random-detect dscp af31 50 64
! Tunes WRED min and max drop-thresholds for AF31/26 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af32 45 64
! Tunes WRED min and max drop-thresholds for AF32/28 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af33 40 64
! Tunes WRED min and max drop-thresholds for AF33/30 to 40 and 64 packets
Router(config-pmap-c)# class CRITICAL-DATA
Router(config-pmap-c)# bandwidth percent 24
! Provisions 24% CBWFQ for CRITICAL-DATA class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on CRITICAL-DATA class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on CRITICAL-DATA class
Router(config-pmap-c)# random-detect dscp af11 50 64
! Tunes WRED min and max drop-thresholds for AF11/10 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af12 45 64
! Tunes WRED min and max drop-thresholds for AF12/12 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af13 40 64
! Tunes WRED min and max drop-thresholds for AF13/14 to 40 and 64 packets
Router(config-pmap-c)# random-detect dscp af21 50 64
! Tunes WRED min and max drop-thresholds for AF21/18 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af22 45 64
! Tunes WRED min and max drop-thresholds for AF22/20 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af23 40 64
! Tunes WRED min and max drop-thresholds for AF23/22 to 40 and 64 packets
Router(config-pmap-c)# random-detect dscp af41 50 64
! Tunes WRED min and max drop-thresholds for AF41/34 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af42 45 64
! Tunes WRED min and max drop-thresholds for AF42/36 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af43 40 64
! Tunes WRED min and max drop-thresholds for AF43/38 to 40 and 64 packets
Router(config-pmap-c)# class SCAVENGER
Router(config-pmap-c)# bandwidth percent 1
! Constrains Scavenger class to 1% CBWFQ
Router(config-pmap-c)# class class-default
Router(config-pmap-c)# bandwidth percent 25
! Provisions 25% CBWFQ for default (Best-Effort) class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on default (Best-Effort) class
Router(config-pmap-c)# queue-limit 128 packets
! Expands queue-limit to 128 packets
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on default (Best-Effort) class
Router(config-pmap-c)# random-detect dscp default 100 128
! Tunes WRED min and max drop-thresholds for DF/0 to 100 and 128 packets
This policy is more granular for the realtime applications like video, streaming and signaling for these protocols.
Finally this is the 12 class model.
! This section configures the class-maps
! (eleven class maps are explicitly defined and one is default)
Router(config)# class-map match-all VOICE
Router(config-cmap)# match dscp ef
! Matches VoIP
Router(config)# class-map match-all BROADCAST-VIDEO
Router(config-cmap)# match dscp cs5
! Matches Broadcast Video
Router(config)# class-map match-all REALTIME-INTERACTIVE
Router(config-cmap)# match dscp cs4
! Matches Realtime-Interactive
Router(config)# class-map match-all NETWORK-CONTROL
Router(config-cmap)# match dscp cs6
! Matches Network Control
Router(config)# class-map match-all SIGNALING
Router(config-cmap)# match dscp cs3
! Matches Signaling
Router(config)# class-map match-all NETWORK-MANAGEMENT
Router(config-cmap)# match dscp cs2
! Matches Network Management
Router(config)# class-map match-any MULTIMEDIA-CONFERENCING
Router(config-cmap)# match dscp af41
Router(config-cmap)# match dscp af42
Router(config-cmap)# match dscp af43
! Matches Multimedia-Conferencing
! One match statement per Drop Precedence increases visibility
Router(config)# class-map match-any MULTIMEDIA-STREAMING
Router(config-cmap)# match dscp af31
Router(config-cmap)# match dscp af32
Router(config-cmap)# match dscp af33
! Matches Multimedia-Streaming
! One match statement per Drop Precedence increases visibility
Router(config)# class-map match-any TRANSACTIONAL-DATA
Router(config-cmap)# match dscp af21
Router(config-cmap)# match dscp af22
Router(config-cmap)# match dscp af23
! Matches Transactional-Data
! One match statement per Drop Precedence increases visibility
Router(config)# class-map match-any BULK-DATA
Router(config-cmap)# match dscp af11
Router(config-cmap)# match dscp af12
Router(config-cmap)# match dscp af13
! Matches Bulk-Data
! One match statement per Drop Precedence increases visibility
Router(config)# class-map match-all SCAVENGER
Router(config-cmap)# match dscp cs1
! Matches Scavenger
! This section configures the 12-Class policy-map
Router(config)# policy-map WAN-EDGE-12-CLASS
Router(config-pmap)# class VOICE
Router(config-pmap-c)# priority percent 10
! Provisions 10% LLQ to VOICE class (multi-LLQ policy)
Router(config-pmap-c)# class BROADCAST-VIDEO
Router(config-pmap-c)# priority percent 10
! Provisions 10% LLQ to BROADCAST-VIDEO class (multi-LLQ policy)
Router(config-pmap-c)# class REALTIME-INTERACTIVE
Router(config-pmap-c)# priority percent 13
! Provisions 13% LLQ to REALTIME-INTERACTIVE class (multi-LLQ policy)
Router(config-pmap-c)# class NETWORK-CONTROL
Router(config-pmap-c)# bandwidth percent 2
! Provisions 2% CBWFQ to NETWORK-CONTROL class
Router(config-pmap-c)# class SIGNALING
Router(config-pmap-c)# bandwidth percent 2
! Provisions 2% CBWFQ to SIGNALING class
Router(config-pmap-c)# class NETWORK-MANAGEMENT
Router(config-pmap-c)# bandwidth percent 3
! Provisions 3% CBWFQ to NETWORK-MANAGEMENT class
Router(config-pmap-c)# class MULTIMEDIA-CONFERENCING
Router(config-pmap-c)# bandwidth percent 10
! Provisions 10% CBWFQ to MULTIMEDIA-CONFERENCING class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on MULTIMEDIA-CONFERENCING class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on MULTIMEDIA-CONFERENCING class
Router(config-pmap-c)# random-detect dscp af41 50 64
! Tunes WRED min and max drop-thresholds for AF41/34 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af42 45 64
! Tunes WRED min and max drop-thresholds for AF42/36 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af43 40 64
! Tunes WRED min and max drop-thresholds for AF43/38 to 40 and 64 packets
Router(config-pmap-c)# class MULTIMEDIA-STREAMING
Router(config-pmap-c)# bandwidth percent 10
! Provisions 10% CBWFQ to MULTIMEDIA-STREAMING class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on MULTIMEDIA-STREAMING class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on MULTIMEDIA-STREAMING class
Router(config-pmap-c)# random-detect dscp af31 50 64
! Tunes WRED min and max drop-thresholds for AF31/26 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af32 45 64
! Tunes WRED min and max drop-thresholds for AF32/28 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af33 40 64
! Tunes WRED min and max drop-thresholds for AF33/30 to 40 and 64 packets
Router(config-pmap-c)# class TRANSACTIONAL-DATA
Router(config-pmap-c)# bandwidth percent 10
! Provisions 10% CBWFQ to TRANSACTIONAL-DATA class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on TRANSACTIONAL-DATA class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on TRANSACTIONAL-DATA class
Router(config-pmap-c)# random-detect dscp af21 50 64
! Tunes WRED min and max drop-thresholds for AF21/18 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af22 45 64
! Tunes WRED min and max drop-thresholds for AF22/20 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af23 40 64
! Tunes WRED min and max drop-thresholds for AF23/22 to 40 and 64 packets
Router(config-pmap-c)# class BULK-DATA
Router(config-pmap-c)# bandwidth percent 4
! Provisions 4% CBWFQ to BULK-DATA class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on BULK-DATA class
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on BULK-DATA class
Router(config-pmap-c)# random-detect dscp af11 50 64
! Tunes WRED min and max drop-thresholds for AF11/10 to 50 and 64 packets
Router(config-pmap-c)# random-detect dscp af12 45 64
! Tunes WRED min and max drop-thresholds for AF12/12 to 45 and 64 packets
Router(config-pmap-c)# random-detect dscp af13 40 64
! Tunes WRED min and max drop-thresholds for AF13/14 to 40 and 64 packets
Router(config-pmap-c)# class SCAVENGER
Router(config-pmap-c)# bandwidth percent 1
! Constrains Scavenger to 1% CBWFQ
Router(config-pmap-c)# class class-default
Router(config-pmap-c)# bandwidth percent 25
! Provisions 25% CBWFQ for default (Best-Effort) class
Router(config-pmap-c)# fair-queue
! Enables fair-queuing pre-sorter on default (Best-Effort) class
Router(config-pmap-c)# queue-limit 128 packets
! Expands queue-limit to 128 packets
Router(config-pmap-c)# random-detect dscp-based
! Enables DSCP-based WRED on default (Best-Effort) class
Router(config-pmap-c)# random-detect dscp default 100 128
! Tunes WRED min and max drop-thresholds for DF/0 to 100 and 128 packets
This policy has even more classes for interactive traffic and also more classes for different types of data and a management class.
Finally you have to apply the policy to an interface like this.
int gix/x service-policy output WAN-EDGE-12-CLASS
Here is a link to WAN QoS CVD.
Your question's pretty broad. There's a lot of different commands you can use to troubleshoot and monitor QoS, so I'll focus on the primary question you have, which is how to reasonably verify your QoS configuration is working and how to read the policy-map interface output.
The only true way to verify that QoS is working is to hook up a traffic generator and monitor your drop rate in various queues. Since that isn't typically feasible, particularly in a production environment, all you can really do is verify that the traffic is being marked and classified properly.
What you're really looking for, when it comes to verifying if your QoS configuration is working, is for the counters in the policy-map interface command to increment.
So, for example, in the output your provided:
Class-map: VOICE (match-any)
3860628 packets, 1070196895 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: protocol sip
97348 packets, 49867304 bytes
5 minute rate 0 bps
Match: protocol rtp
3763280 packets, 1020329591 bytes
5 minute rate 0 bps
Match: access-group name NEC-PBX
0 packets, 0 bytes
5 minute rate 0 bps
Priority: 40% (340 kbps), burst bytes 8500, b/w exceed drops: 5
You can see that you're seeing packets under SIP and RTP, but not NEC-PBX. If you know you're getting SIP and RTP traffic across a link, you should see the packet counts increment and that's a reasonable way to know that your configuration is basically working.
Best Answer
Probably you are looking for things like:
Edit:
Depending on your IOS version, you may need to use these commands: