Can a Cisco guru explain this please?

iaind

iaind

iaind

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I'm just in the process of configuring a new Cisco 3560 switch to run our voice and data at a new site, mostly copying the config from the switches here at our main office.

The new office is going to be on a 50mb microwave link, with about 5ms latency - running Cisco VOIP and Citrix for 18 users, so plenty bandwidth. I'm just considering QOS, to ensure I dont need to make a change, but the Cisco QOS configuration is waaaaay over my head.

Can someone explain to me what this means and whether I should make any changes given the bandwidth/latency of the link?

Thanks!

!
!
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
Click to expand...

And the port config:

!
interface GigabitEthernet0/2
switchport access vlan 2
switchport voice vlan 200
srr-queue bandwidth share 10 10 60 20
srr-queue bandwidth shape 10 0 0 0
queue-set 2
mls qos trust device cisco-phone
mls qos trust cos
auto qos voip cisco-phone
spanning-tree portfast
Click to expand...

Thanks all!
 
I could explain but unfortunetly im lazy, the link below will help greatly

http://blog.internetworkexpert.com/2008/03/03/bridging-the-gap-between-3550-and-3560-qos-part-i/

In short the first secton defines global QoS settings for the switch, DSCP - COS Mappings, Queue Depth etc. The second snippet defines a per port QoS configuration for a port connected to a Cisco phone, these port roles have been predefined by Cisco based on best practise and generally dont need to be changed.
 
Yep - all that's done to Cisco recommended stuff - I think it sets it all up when you enter this under a port "auto qos voip cisco-phone" when you first enter it it takes ages while it does all the MLS stuff of the switch...
 
Are you telling me I've just sat there typing all that line by line when it would do it automatically? Fail.

Is there anything else I should configure given the network setup? I'm thinking that given the bandwidth, I may as well keep it the same as the lan. Its an unrouted connection so I was just going to set up a port each end as a dot1q trunk.
 
This reminds me of my first ccna exam which I sat after a year of no work. They asked me to "make a diagram of how to setup a network between a and b" and instead of (rightly) typing something like the above, i drew a diagram with lines, arrows and rectangles, LOL.
 
I deliberately opted not to copy/paste into a new config and import by tftp, because I thought it might help me learn what was going on!

Never mind, live and learn! :D
 
:D

I think you'll be ok with dot1q trunking - IIRC there's a command to set the QOS for the trunk too. This way the voice should get preference over data, but you shouldn't really notice till you hit congestion anyway...
 
The only thing I can see causing conjestion on the trunk is large print/scanning jobs... surely if voice is getting priority on all the ports, it's going to have overall priority on the trunk anyway?
 
yes, but as I understand it (which I probably don't very well!) only to a point - as all you're doing on the switch is trusting the phone QOS tagging and then setting the software queues on the switch - voice will have priority, but if it gets overwhelmed by something, there's not really a method in-place to protect it.

Shouldn't really be much of an issue if it's only for a small amount of voice users and citrix traffic. Scanning could be completed out of hours to reduce that problem...
 
I meant scanning of documents, not virus scanning :)

Our MFPs can take a feeder full of pages and dump a single huge PDF onto an SMB share....
 
iaind said:
Are you telling me I've just sat there typing all that line by line when it would do it automatically? Fail.

Is there anything else I should configure given the network setup? I'm thinking that given the bandwidth, I may as well keep it the same as the lan. Its an unrouted connection so I was just going to set up a port each end as a dot1q trunk.
Click to expand...

To be honest for most deployments you can use Cisco Network Assistant which will take care pretty much all the config for you, definately one of their better GUI tools.

You can get the latest version 5.5 for free from Cisco.com.
 
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