Qos help

[jeevak mukadam]

Hello,

We are using 2960s switch on which QOS was configured as follows.

mls qos map policed-dscp  0 10 18 to 8
mls qos map cos-dscp 0 8 16 24 32 46 48 56
mls qos srr-queue output cos-map queue 1 threshold 3 4 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 3 32 33 40 41 42 43 44 45
mls qos srr-queue output dscp-map queue 1 threshold 3 46 47
mls qos srr-queue output dscp-map queue 2 threshold 1 16 17 18 19 20 21 22 23
mls qos srr-queue output dscp-map queue 2 threshold 1 26 27 28 29 30 31 34 35
mls qos srr-queue output dscp-map queue 2 threshold 1 36 37 38 39
mls qos srr-queue output dscp-map queue 2 threshold 2 24
mls qos srr-queue output dscp-map queue 2 threshold 3 48 49 50 51 52 53 54 55
mls qos srr-queue output dscp-map queue 2 threshold 3 56 57 58 59 60 61 62 63
mls qos srr-queue output dscp-map queue 3 threshold 3 0 1 2 3 4 5 6 7
mls qos srr-queue output dscp-map queue 4 threshold 1 8 9 11 13 15
mls qos srr-queue output dscp-map queue 4 threshold 2 10 12 14
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 1 buffers 15 25 40 20

user port:

interface GigabitEthernet1/0/7
description ### DATA ZONE - 1 ###
switchport access vlan 31
switchport mode access
switchport voice vlan 131
switchport port-security maximum 11
switchport port-security
switchport port-security aging time 2
switchport port-security violation restrict
switchport port-security aging type inactivity
ip arp inspection limit rate 100
srr-queue bandwidth share 1 30 35 5
queue-set 2
priority-queue out
mls qos trust device cisco-phone
mls qos trust cos
macro description AccessEdgeQoS
auto qos voip cisco-phone
spanning-tree portfast
spanning-tree bpduguard enable
service-policy input AUTOQOS-SRND4-CISCOPHONE-POLICY
ip verify source
ip dhcp snooping limit rate 100

As per my understanding  2960s switch do not support ingress queuing.Here all qos mappng commands are configured as egress queuing but service -policy on user port configured as input policy.

I need help on this.

[cmarva]

you would have to look at the service policy. With srnd4, when you enter(ed) auto qos voip cisco-phone on this interface, the service policy gets applied. I believe all it does is match markings and then set input rate limits, but I haven't looked over this in a while and am going from memory.

chris

[jeevak mukadam]

Hello Chris,

Thank you for your reply,

You r right with auto qos voip cisco-phone command applied service-policy.But here service policy applied as inbound direction where ingress queuing on 2960 switch is not supportable,it must be in output direction?

[cmarva]

Jeevak,

the service policy is not actually queueing. The queues are assigned on egress via the following under the interface:

srr-queue bandwidth share 1 30 35 5

queue-set 2

priority-queue out

the service policy is doing classification/marking on ingress, and also policing to specific bandwidths. That's perfectly fine,

because based on the ingress markings, it will get assigned to a transmit queue elsewhere (IE-uplink to network, or other edge port on the switch, if that's where the destination is).

At least that's my understanding - chris

[Joseph W. Doherty]

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Posting

What Chris wrote is basically correct, although to clarify, either there's just one egress queue, when QoS is disabled, or four egress queues, when QoS enabled.

The interface configurations noted by Chris, define the dequeuing scheduling treatment between the four queues and which queue-set to use for other resource configuration options (defined globally).