auto qos voip cisco-phone

W T F?

Is this a normal QoS config on a 2950?

First off, here is the config on the access port after configuring auto qos voip cisco-phone:

interface FastEthernet0/14
 switchport access vlan 947
 switchport mode access
 switchport nonegotiate
 switchport voice vlan 432
 switchport port-security maximum 2
 switchport port-security
 switchport port-security violation restrict
 switchport port-security mac-address sticky
 switchport port-security mac-address sticky 0004.f202.70ec vlan voice
 switchport port-security mac-address sticky 0018.8bc6.b9e3
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape  10  0  0  0
 mls qos trust device cisco-phone
 mls qos trust cos
 auto qos voip cisco-phone
 spanning-tree portfast

And here is the QoS config that was generated:

mls qos map cos-dscp 0 8 16 26 32 46 48 56
mls qos srr-queue input bandwidth 90 10
mls qos srr-queue input threshold 1 8 16
mls qos srr-queue input threshold 2 34 66
mls qos srr-queue input buffers 67 33
mls qos srr-queue input cos-map queue 1 threshold 2  1
mls qos srr-queue input cos-map queue 1 threshold 3  0
mls qos srr-queue input cos-map queue 2 threshold 1  2
mls qos srr-queue input cos-map queue 2 threshold 2  4 6 7
mls qos srr-queue input cos-map queue 2 threshold 3  3 5
mls qos srr-queue input dscp-map queue 1 threshold 2  9 10 11 12 13 14 15
mls qos srr-queue input dscp-map queue 1 threshold 3  0 1 2 3 4 5 6 7
mls qos srr-queue input dscp-map queue 1 threshold 3  32
mls qos srr-queue input dscp-map queue 2 threshold 1  16 17 18 19 20 21 22 23
mls qos srr-queue input dscp-map queue 2 threshold 2  33 34 35 36 37 38 39 48
mls qos srr-queue input dscp-map queue 2 threshold 2  49 50 51 52 53 54 55 56
mls qos srr-queue input dscp-map queue 2 threshold 2  57 58 59 60 61 62 63
mls qos srr-queue input dscp-map queue 2 threshold 3  24 25 26 27 28 29 30 31
mls qos srr-queue input dscp-map queue 2 threshold 3  40 41 42 43 44 45 46 47
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 3  2 4
mls qos srr-queue output cos-map queue 4 threshold 2  1
mls qos srr-queue output cos-map queue 4 threshold 3  0
mls qos srr-queue output dscp-map queue 1 threshold 3  40 41 42 43 44 45 46 47
mls qos srr-queue output dscp-map queue 2 threshold 3  24 25 26 27 28 29 30 31
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  16 17 18 19 20 21 22 23
mls qos srr-queue output dscp-map queue 3 threshold 3  32 33 34 35 36 37 38 39
mls qos srr-queue output dscp-map queue 4 threshold 1  8
mls qos srr-queue output dscp-map queue 4 threshold 2  9 10 11 12 13 14 15
mls qos srr-queue output dscp-map queue 4 threshold 3  0 1 2 3 4 5 6 7
mls qos queue-set output 1 threshold 1 138 138 92 138
mls qos queue-set output 1 threshold 2 138 138 92 400
mls qos queue-set output 1 threshold 3 36 77 100 318
mls qos queue-set output 1 threshold 4 20 50 67 400
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 41 68 100 272
mls qos queue-set output 2 threshold 4 42 72 100 242
mls qos queue-set output 1 buffers 10 10 26 54
mls qos queue-set output 2 buffers 16 6 17 61
mls qos

Needless to say, having zero practical VOIP or QoS experience, I have no idea how to even interpret this mess....

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Comments

keenon

auto-qos can generate alot of code on the switch not including the port as well.. i'm however curious to these statements on the port

switchport port-security maximum 2
switchport port-security
switchport port-security violation restrict
switchport port-security mac-address sticky
switchport port-security mac-address sticky 0004.f202.70ec vlan voice
switchport port-security mac-address sticky 0018.8bc6.b9e3

this part i haven't ever seen unless manually added

are you actually using cisco phones is my question as well b/c this statement '

mls qos trust device cisco-phone

this will only trust a cisco phone and all other voip phone venders stuff will be retagged as default and you will experience issues if it crosses an link with alot of load on it.

all of the stuff in the second part is about normal

here are 2 links on qos

auto qos
http://cisco.com/en/US/tech/tk543/tk759/tk879/tsd_technology_support_technology_information.html

qos
http://cisco.com/en/US/tech/tk389/tk813/tsd_technology_support_technology_information.html

cisco_trooper

yeah, the port-security is unrelated to the qos configuration. the phones are Polycom that participate in CDPv2....

nel

ive been rolling out voip support on our 3560's and thats the same stuff i get. However i havent got to th epoint where i know what it all means

keenon

cisco_trooper wrote:

yeah, the port-security is unrelated to the qos configuration. the phones are Polycom that participate in CDPv2....

i would suggest double checking it that the voip packets aren't be retagged as default..if not keep it moving

kpjungle

Its similar to what I get, even though I think it might differ depending on what sort/type of queue's the switch support. But it quickly becomes a mess

tomset

Most of that code is just a highly-tweaked QoS config that was coded by Cisco to fit most VoIP situations. I wouldn't worry about understanding it all unless you (1) want to dig pretty deep into QoS or (2) are experiencing problems with the auto QoS settings

cisco_trooper

Ok, then, that being said, what would a non-highly tweaked config look like? All I am supporting on the access link is VOIP and standard data. So I guess all I really need (with my limited understanding of the guts of QoS) is for VLAN 432 traffic to be placed in the priority queue....

dtlokee

If you apply the Cisco-phone template it will add the port security configuration also.

cisco_trooper

...And you know what else...I read somewhere, I can't remember where because it was yesterday, that queue 4 was the priority queue. BUT, this config appears to assign COS 5 to output queue 1. What gives???

mls qos srr-queue input cos-map queue 2 threshold 3  3 5 
mls qos srr-queue output cos-map queue 1 threshold 3  5

dtlokee

cisco_trooper wrote:
...And you know what else...I read somewhere, I can't remember where because it was yesterday, that queue 4 was the priority queue. BUT, this config appears to assign COS 5 to output queue 1. What gives???
mls qos srr-queue input cos-map queue 2 threshold 3  3 5 
mls qos srr-queue output cos-map queue 1 threshold 3  5 

That is hardware dependant, some switches usr Queue 1 as the PQ and some use Q4 as the PQ. I think the 2950/3550 use Q4 and the 2960/3560 use Q1 so that would seem to make the autoqos configuration invalid you posted invalid.

http://www.cisco.com/en/US/docs/switches/lan/catalyst2950/software/release/12.1_22_ea11x/configuration/guide/swqos.html#wp1136968

In Cisco IOS Release 12.1(12c)EA1 or later, beginning in privileged EXEC mode, follow these steps to enable the expedite queue (queue 4) and assign WRR priority to the remaining queues

Good thing Cisco is consistent

cisco_trooper

keenon wrote:

cisco_trooper wrote:

yeah, the port-security is unrelated to the qos configuration. the phones are Polycom that participate in CDPv2....

i would suggest double checking it that the voip packets aren't be retagged as default..if not keep it moving

This 2950 has an uplink to a 6513. I sniffed the traffic coming in to that 6513 interface and the packets are being tagged with the correct values. I used OMNIPeek to identify the voice traffic and check the QoS values. The one question that still remains is the queues in effect on the 2950....I'm checking out the link DT provided now...

cisco_trooper

dtlokee wrote:

That is hardware dependant, some switches usr Queue 1 as the PQ and some use Q4 as the PQ. I think the 2950/3550 use Q4 and the 2960/3560 use Q1 so that would seem to make the autoqos configuration invalid you posted invalid.

That's what I thought too, but that config came straight from my 2950, which is why I'm having questions..I'm going to check out your link and see if something clicks for me.

Here is the image I'm using: c2950-i6q4l2-mz.121-22.EA11.bin

Found this: http://www.cisco.com/en/US/tech/tk389/tk813/technologies_q_and_a_item09186a00804976d3.shtml#qa12

cisco_trooper

Shaped Round Robin was used in the auto-qos generation. I've been going over all this for about half the day and I think I've got it all worked out in my head now....

FYI....SRR uses input queue 2 as the priority queue by default...

Netwurk

I'll throw in this little bit of lab advice (mentioning lab since most likely no one would do this in production)...

If you "go back in time" STP wise (like moving from MST to PVST), I've found that all those auto qos settings wind up effectively shutting down the affected ports.

Temporarily took down my wife's wireless access by doing that.

Solution was to undo every qos setting - a little time consuming, but wound up being necessary to keep peace in the house

cisco_trooper

Netwurk wrote:

I'll throw in this little bit of lab advice (mentioning lab since most likely no one would do this in production)...

If you "go back in time" STP wise (like moving from MST to PVST), I've found that all those auto qos settings wind up effectively shutting down the affected ports.

Temporarily took down my wife's wireless access by doing that.

Solution was to undo every qos setting - a little time consuming, but wound up being necessary to keep peace in the house

Do you know what the problem was, more specifically? Did the QoS prevent BPDUs from being processed effectively?

Netwurk

cisco_trooper wrote:

Do you know what the problem was, more specifically? Did the QoS prevent BPDUs from being processed effectively?

I honestly don't know. At the time, I just wanted to get wireless running.

Would have had to log the whole process if I did it at work. Of course, I would probably be out a job if I was randomly changing the STP landscape.

cisco_trooper

Yeah, so I was revisiting this topic today and noticed that I said this was a 2950. This is actually a 2960 running c2960-lanbase-mz.122-25.SEE2 .....

Anyway, being a 2960 explains why I have the shaped-round-robin feature rather than the weighted-round-robin feature of the 2950. Also the 2950 does not appear to support auto-qos on the ethernet interfaces..

Overall the QoS configuration on the 2950 appears to be extremely simplistic when compared to the 2960. I don't seem to be able to even map CoS values to DSCP values on the 2950.......

Anyway, I must have been in tunnel-vision....the rest of my access switches are the 2950s....

Anyone have any additional thoughts now that I've cleared this up.....???

cisco_trooper

Man, all these switches are SI. What a crock.....

Netwurk

My lab has 2924's, 2950's, and 3550's

The only switch I have that can do advanced QOS is the 3550's

I don't think a 2960 can do the kind of QOS you need for the BCMSN, but don't have one here or at work so I don't know

cisco_trooper

Yeah, the 2960 I was working with I didn't realize was a 2960 because I didn't know we had any. This whole project was more work related and not necessarily geared toward BCMSN study. Are your 2950s the EI models? According to some documentation I've read and according to the End-to-End QoS Design book I mentioned somewhere the EI model will do some of the class-based queueing/policing, etc.....

I would like to get my hands on one to see EXACTLY what it can do...

Netwurk

I just have a plain old 2950-24, although they're all decent and they can use something very close to latest command set.

Actually had an EI on order a couple of months ago, but it was from an ebay guy who decided to cash in on his 100% rating. He was just collecting money from folks and not shipping. It took a while, but I got my money back from Paypal. Traded a lot of e-mails with the other people he conned.

Ebay isn't what it used to be in my opinion. Everything is overly-automated now, with no common sense oversight.