moving from 2950 to a 3560x non poe swith QOS help!

itdaddy

wrr-queue bandwidth (does not work in global config mode on this new 3560x?)

mls qos cos 6 (works and I can enter it but when I save it it never saves)


hey guys I am noob when it comes to QOS but I am changing out a switch
and there are not too many unfamilar configs but this is the only QOS I see on the switch

(global config mode)
wrr-queue bandwidth 25 25 25 0


(interfaces)
mls qos cos 6 (works but will not save?)
mls qos trust cos (works and does save)

I have no clue wha they do i am only copying them over port by port but
on the new 3560x


any help on this why or what I should use instead of the msl qos cos 6 and why it doesnt save? when I save the config. and what do I used instead of the wrr-queue wt wt wt wt

thanks so much

dtlokee

The 3560X uses a more advanced QoS mechanism than the 2950 known as SRR or shaped round robin. This means that the majority of the commands are still available but now need to be "srr" instead of "wrr" but there are some exceptions. When enabling QoS you first must enable it globally on the switch with the command "mls qos" if you have not done that the interface commands might be ignored. You can try the interface command "srr-queue bandwidth share 25 25 25 0" to set up your queing rates.

itdaddy

description Connection to EnterpriseI
switchport access vlan 121
switchport mode access
mls qos cos 6
mls qos trust cos
spanning-tree portfast

wrr-queue bandwidth 25 25 25 0

description Connection to EnterpriseI
switchport access vlan 121
switchport mode access
mls qos trust cos
spanning-tree portfast

Cannot do the Global command: wrr-queue bandwidth 25 25 25 0

Just to let you know it is on a non POE switch.
So what do you think would be the equivalent commands to replace them.
I have no clue and there is not many really. And is the auto qos?

I just need a few tips or good references. Do I need to run the srr command on all interfaces since wrr was a global command ( and in or out ). And which interfaces does this refrence.
I think the mls qos cos 6 tags the voice traffic so it is prioritized??? thanks man I appreciate your help. I just need to figure out what the equivalent commands would be to work right? Thank you.

itdaddy

will this be equivalent? The old wrr- command was on a 2950. this new switch is a 3560x
so will below be equivalent. Globally place below and then

priority-queue out
mls qos trust cos

I am just not sure about the mls qos cos 6 command. What does this do?
both interfaces that this is on leads to our voice controllers and servers.
So doesn't that command tag the voice to be priority 6?

mls qos srr-queue input cos-map queue 1 threshold 1 5
mls qos srr-queue input cos-map queue 2 threshold 1 6
mls qos srr-queue input dscp-map queue 1 threshold 1 40 41 42 43 44 45 46 47
mls qos srr-queue input dscp-map queue 2 threshold 1 48 49 50 51 52 53 54 55
mls qos srr-queue output cos-map queue 1 threshold 1 6
mls qos srr-queue output cos-map queue 4 threshold 1 5
mls qos srr-queue output dscp-map queue 1 threshold 1 48 49 50 51 52 53 54 55
mls qos srr-queue output dscp-map queue 4 threshold 1 40 41 42 43 44 45 46 47
mls qos

interface GigabitEthernet0/10
switchport access vlan 101
switchport trunk encapsulation dot1q
switchport trunk native vlan 101
switchport trunk allowed vlan 101,121
switchport mode trunk
priority-queue out
mls qos trust cos
spanning-tree portfast

cisco_trooper

Off topic but the native VLAN would ideally be a VLAN that is not in use anywhere on the network and wouldn't be allow to traverse the trunk...

dtlokee

The "mls qos cos 6" command sets the cos (802.1p) to a value of 6. Assuming that you are also trusting this COS then it will be retained on the frame and will be mapped into a DSCP value of 48 (by default). It is not typical to use a COS of 6 for traffic that is not "internetwork control" type traffic such as spanning tree bpdus, routing protocols, etc but if it works for your environment then go with it. Typically voice traffic is assigned a COS of 5 and mapped to DSCP EF (46).

mls qos srr-queue output dscp-map queue 1 threshold 1 48 49 50 51 52 53 54 55
mls qos srr-queue output dscp-map queue 4 threshold 1 40 41 42 43 44 45 46 47

Did you take the WRR configuration and change the WRR to SRR in that example? One other difference between WRR and SRR is that WRR used queue 4 for the priority queue and SRR uses queue 1 for the priority queue. In your case you're mapping voice to COS 6 wich is mapped to DSCP 48 so you are putting it into queue 1 which in this case is the priority queue. It's possible that your old configuration was incorrectly putting voice into q1 which is not the priority queue.

itdaddy

dtlokee


I am just mirgating the 2950 to a 3560x which I see uses the new srr-queue command.
It only has the 3 command lines used. I just need the equvalent? thanks