Converting QoS settings from 12.2 to 16.9

[Maldini]

Hello, hoping someone can help or point me in the right direction at least!

I am replacing a 3750 stack (v12.2) at one of our sites with a stack of new 9200L switches (v16.9) - the majority of the config I've been able to transfer across with a couple of changes to commands that have changed between the IOS versions.  However, the QoS settings I am struggling with.  At the moment the only QoS requirement I have is to prioritise voice traffic and the handsets (not Cisco) are currently tagging their traffic with DSCP=46.

The relevant parts from the current config are shown below (in bold):

!
mls qos map policed-dscp 0 10 18 24 38 46 to 0
mls qos map policed-dscp 34 to 38
mls qos map cos-dscp 0 14 22 24 34 46 48 56
mls qos queue-set output 1 buffers 15 25 40 20
mls qos queue-set output 2 buffers 16 6 61 17
mls qos queue-set output 1 threshold 1 100 100 50 200
mls qos queue-set output 1 threshold 2 125 125 100 400
mls qos queue-set output 1 threshold 3 100 100 100 400
mls qos queue-set output 1 threshold 4 60 150 50 200
mls qos queue-set output 2 threshold 1 149 149 100 149
mls qos queue-set output 2 threshold 2 118 118 100 235
mls qos queue-set output 2 threshold 3 42 72 100 242
mls qos queue-set output 2 threshold 4 41 68 100 272
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 3 3 6 7
mls qos srr-queue output cos-map queue 3 threshold 1 0
mls qos srr-queue output cos-map queue 4 threshold 1 1 2
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 2 18 26
mls qos srr-queue output dscp-map queue 2 threshold 3 24 48 56
mls qos srr-queue output dscp-map queue 3 threshold 1 0 1 2 3 4 5 6 7
mls qos srr-queue output dscp-map queue 3 threshold 2 9 11 12 13 14 15
mls qos srr-queue output dscp-map queue 3 threshold 3 8 10
mls qos srr-queue output dscp-map queue 4 threshold 1 16 20 22
mls qos srr-queue output dscp-map queue 4 threshold 2 38 30
mls qos srr-queue output dscp-map queue 4 threshold 3 36 28
mls qos
!

!
interface GigabitEthernet1/0/1
description *** Uplink to MPLS Primary Router ***
switchport access vlan 20
srr-queue bandwidth share 30 10 30 30
srr-queue bandwidth shape 3 0 0 0
mls qos trust dscp
storm-control broadcast level 2.00
storm-control multicast level 2.00
spanning-tree bpduguard disable
!
interface range GigabitEthernet1/0/2 - 48
description *** Access Port, Device and/or Phone ***
switchport access vlan 2
switchport mode access
switchport voice vlan 10
srr-queue bandwidth share 3 10 42 35
srr-queue bandwidth shape 30 0 0 0
storm-control broadcast level 2.00
storm-control multicast level 2.00
mls qos trust dscp
no snmp trap link-status
spanning-tree portfast
!

If possible I'd like to keep things as simple as possible and use auto QoS.

Could I simply replace mls qos trust dscp on the interfaces with auto qos trust dscp and forget about all the other lines of config above?

Thanks in advance.

[cmarva · Accepted solution]

in my experience, all of the queue set commands and such have "appeared" after the way I typically configure a switch, by doing:

auto qos srnd4

!

int range g1/0/1 - 24

auto qos voip cisco-phone

that's for IOS. The methodology is still good for the 9200s, except the resulting config will look a lot different. It will still auto populate once you enter the relevant commands. Bottom line is, whatever the config looks like, as long as it matches or trusts dscp 46 (either explicitly or by trust dscp) you should be good to go.